fraunhofer in benediktbeuern - glassworks and workshop · local glassworks into a profitable...

Fraunhofer in BenediktbeuernGlassworks and Workshop

Fraunhofer in Benediktbeuern Glassworks and Workshop

Contents

Dr. Wolfgang Jahn “He brought us closer to the stars.”The life of Joseph von Fraunhofer 4

Joseph von Fraunhofer Time line 16

Dr. Josef KirmeierResearch and production Glassworks and Optical Institute in Benediktbeuern 18

Pater Prof. Dr. Dr. Leo WeberJoseph von Utzschneider and Joseph von Fraunhofer at the former Benedictine monastery of Benediktbeuern, 1805 –1818 32

Christoph MewesThe exhibition: Glassworks and workshop 40

Carl R. PreyßFraunhofer’s significance 44

References 47

Editorial notes 48

Joseph von Fraunhofer’s research in the field of optics was pioneering, leav-ing a lasting mark on this branch oftechnology. His work earned him wide-spread acclaim among the scientificcommunity. Yet he also set new stan-dards as an inventor and entrepreneur.

At the start of the 19th century, Fraunhofer‘s workplace – and as suchthe birthplace of the modern-day glass industry – was in Benediktbeuern.Holding responsibility for research and production, Fraunhofer turned thelocal glassworks into a profitable busi-ness. He managed to solve the majortechnical problems surrounding glassproduction in his day by understandinghow to effectively bring together three elements: Research, the conver-sion of research results into practicalapplications and the marketing of fin-ished products.

Fraunhofer embraced this principlemost clearly with his refractors – largeastronomical telescopes whose lenseswere a superb technical achievementat the time. One of these telescopes,made around 1820 in the workshoprun by Fraunhofer and Utzschneider,with a lens measuring 163 millimetersin diameter and a focal length of 2.5 meters, now graces the foyer ofthe Fraunhofer-Gesellschaft head -quarters in Munich.

Joseph von Fraunhofer‘s workshop formanufacturing optical instruments wason show in the Munich Stadtmuseum(city museum) for many years. In 2008,it was moved to the Benediktbeuernglassworks. The fixtures also includedoriginal grinding machinery along withprotective masks to shield the glass-workers from the heat, as well as glasssamples and prisms. Anyone inter -ested in discov ering the achievementsof this brilliant researcher and entre-preneur can now experience his work-ing environment up close, all under a single roof.

We would like to thank the many people that have been involved in thebuilding and extension of the glass-works museum. Particular thanks go toMr. Carl R. Preyß, a founding memberof the Fraunhofer-Gesellschaft. As the person behind the extension work,he has worked tirelessly to bring theproject to a successful conclusion. TheBenediktbeuern monastery provided us with the new facilities, the DeutschesMuseum helped with expert advice,and the Munich Stadtmuseum donatedthe exhibits. Particular support for theextension work came from the spon-sors Dr. Rudolf Pesl from Unterhachingand the Sparkasse Bad Tölz-Wolfrats -hausen Foundation. Our special thanksgo not least to all the authors whosearticles have turned this publicationinto a highly interesting source of infor-mation on Joseph von Fraunhofer, hisachievements and his time.

The products that Fraunhofer manu -factured in Benediktbeuern are nowpart of technology history. Yet thecombination of research, practical ap-plications and an entrepreneurial approach is more important than everin our globalized world. In this respect,Joseph von Fraunhofer's work lives on in today's Fraunhofer-Gesellschaft.

Hans-Jörg BullingerPresident of the Fraunhofer-Gesellschaft

4 Fraunhofer in Benediktbeuern

Dr. Wolfgang Jahn reports on Joseph von Fraunhofer, thehardships suffered during his childhoodand apprenticeship, his achievementsand his acclaimed success as a scientistand entrepreneur.

“Joseph von Fraunhofer is the manthat without ever having regularly at-tended school ... overcame all mannerof obstacles in his vocational training.(...) I hope this life story will inspireother young people to apply the samespirit, whatever their discipline, to become an outstanding member of society. The following outlines Fraunhofer's progressive steps in train-ing, his impact on his business circles, and the wealth of useful knowl-edge he created for the good ofmankind.”

Thus the obituary published in the“Kunst- und Gewerbeblatt des poly-technischen Vereins für das KönigreichBayern”(art and commerce journal of the polytechnic club for the Bavarianempire) in July 1826, when privy councilor Joseph von Utzschneider paid tribute to his long-standing businesspartner Joseph von Fraunhofer, whohad recently passed away.

Early loss of parents

Joseph Fraunhofer was born in Straub-ing on March 6, 1787, the youngest of eleven children of the glazier FranzXaver Fraunhofer and his wife AnnaMaria. The Fraunhofer family, originallyfrom Miesbach, had been based inStraubing since the 18th century. Forseveral generations the Fraunhofershad links to glass production; the grand-father and an uncle had been glaziers.Joseph most certainly worked in his father’s workshop.

He was orphaned at the tender age of 12, following the untimely death ofboth parents. In August 1799, hisguardians sent Joseph to Munich towork as an apprentice for the mirrormaker and decorative glass cutter, Philipp Anton Weichselberger. His ap-prenticeship was marred by difficultieswith his master, who prevented Fraunhofer from reading up on science.

“He brought us closer to the stars.”The life of Joseph von Fraunhofer

The solar spectrum drawn by Joseph von Fraunhofer. Theclearly discernible black absorp-tion lines discovered by Fraunhofer are now known asFraunhofer lines.

“He brought

to the

us closer

Fraunhofer in Benediktbeuern 5

An accident – favorable turn of fate

A tragic event in 1801 proved a de cisiveturning point in Joseph Fraunhofer‘slife. The apprentice was buried in theruins of Weichselberger's house. Thewidespread public interest in the rescuework – prince-elector Maximilian IVJoseph attended in person – broughtFraunhofer into contact with Josephvon Utzschneider,who would from thenon play an important role in his life.

The remainder of his apprenticeshipthrough 1804 was fairly unremarkable.Fraunhofer's endeavors to extend histheoretical and practical knowledge in the field of optics are worthy ofnote. He used part of a donation fromthe prince-elector to buy an opticalgrinding machine. Meanwhile, hemanaged to put his lens-grinding skills to practical use by working for an optician. Fraunhofer remained Weich-selberger‘s assistant through 1806,after an initial attempt to set up in business printing visiting cards hadfailed.

The young Fraunhofer came intocontact with prince-elector Maximilian IV Joseph by chancewhile being rescued from the ruins of his master’s house.

stars.”

Utzschneider had held influential posi-tions in the prince-elector‘s admin -istration before being suspended frompublic office in 1801. He nurturedFraunhofer's thirst for knowledge withtextbooks on mathematics and optics: “In these books he found that aknowledge of pure mathematics wasabsolutely essential to his studies; that is why he also started to studypure mathematics along with optics,becoming familiar with most of its elements through optics”, Utzschneiderwrites in his obituary, claiming thecredit for having discovered and ener-getically nurtured the existing talentsof the young Fraunhofer.


Fraunhofer turns optician

Fraunhofer‘s and Utzschneider‘s pathsdid not cross again until Utzschneidermade Fraunhofer an offer to join him and Liebherr as an optician at the Reichenbach Mathematical-Mechan -ical Institute in 1806. At the time,Fraunhofer had clearly already acquireda good reputation as an optician. Anexamination lasting several days carriedout by Professor Ulrich Schiegg, whohad been a monk in the Ottobeurenmonastery before secularization andwas now working as an astronomer andordinance surveyor, confirmed Fraunhofer‘s talents.

The foundation of the Mathematical-Mechanical Institute was a consquenceof the increased need for optical in-struments in fields such as ordinancesurveying and research in the naturalsciences. Thus the intention from the outset was to manufacture high-quality optical instruments. A distinctlack of suitable glass posed a majorproblem for production. Utzschneidertherefore devoted much of his energiesto pressing ahead with establishing his own manufacturing facility in theformer Benediktbeuern Monastery,under the direction of the Swiss glass-maker Pierre Louis Guinand. The new role taken on by Fraunhofer in the glassworks in Benediktbeuern was to grind the glass produced underGuinand‘s direction.

Although Fraunhofer was still answer-able to Guinand for the time being, his extraordinary talents came to thefore in 1807 when he submitted hisfirst scientific paper. Entitled “Über parabolische Spiegel und Beschreibungkrummliniger Segmente ...” (On par a -bolic mirrors and the description of curvilinear segments ...), it examinedtheories aimed at improving the de-sign of reflecting telescopes.

Left: Joseph von Fraunhofer, researcher,inventor and entrepreneur.Right: Joseph von Utzschneider, one ofBavaria's first industrial entrepre-neurs.

Aerial shot of the Benedikt-beuern monastery taken in 1921.


Research for glass production

Fraunhofer‘s most important task during these years was, however, hisinvolvement in glass production and the processing of glass destinedfor the institute in Munich. It was herethat Fraunhofer‘s methodology became patently clear. The researcher utilizedhis theoretical knowledge to improveand supplement existing methods.Along these lines, he developed a pol-ishing machine to process glass moreprecisely, along with a measurementmethod to control the regular shape oflenses. The success of his approachwas not just based on good ideas butalso on painstaking experimentationaimed at systematically fine-tuning theproduction processes.

Fraunhofer‘s work caused tensionswith Guinand, who was still responsi-ble for supervising the glass meltingprocess, while prompting Utzschneiderto rethink the focus of the Optical In-stitute in Benediktbeuern. The mostpressing problem at the time was howto manufacture glass to the highestpossible standards. Besides the appear-ance of streaks, small particles wouldflake off from the crucible and appearas schlieren in the glass. To improvequality, Guinand had already workedwith an improved stirrer designed toproduce a more even, bubble-free cast.However, the Mathematical-Mechan -ical Institute was receiving more andmore complaints about the poor quality of the glass being supplied, notto mention the long lead-times, a situation that did not bode well eitherfor the business's competitiveness.

Illustration of a glass furnacewith stirrer. This technology decisively helped improve glass quality.


Institute reorganization hands moreresponsibility to Fraunhofer

In 1808 and 1809, Utzschneider reor-ganized the Mathematical-MechanicalInstitute in Munich and the Optical Institute in Benediktbeuern, instigatinga major reallocation of duties. As such, Fraunhofer was now responsiblefor the entire downstream processing,apart from the glass melting processthat remained under Guinand's con-trol. “My job is therefore to supervisethe entire institute, to grind the most important lenses, calculate andcheck the lenses”, is how Fraunhoferdes cribes his role during this period.

The dispute with Guinand only gotworse as Fraunhofer also tried to havea say in the glass melting process. Hitherto, Guinand had kept the precisemelting process a closely guarded industrial secret, with Utzschneider leftto decide who was given access to this valuable information. Utzschneidernow instructed Guinand to brief Fraunhofer on the secrets of the glassmelting process. In 1811, Fraunhoferfinally assumed supervisory responsibil-ities for the glass melting process. This extended, responsible role is alsoreflected in Utzschneider's decision tomake Fraunhofer a partner of the Optical Institute. Fraunhofer believedthe Optical Institute should in futureeffectively become a component sup-plier for the Mathematical-MechanicalInstitute in Munich. The plan would be to manufacture lenses in varioussizes and sufficient quantities withinset delivery times.

View of the inside of the glass-works in Benediktbeuern around1900.

The Swiss glassmaker Pierre LouisGuinand was the first director of the glassworks in Benedikt-beuern. He applied the stirringprocess used for casting bells to glass production.


Better glass for more accurateinstruments

Over the next few years, Fraunhoferfocused on improving the workflowsfor glass processing. Painstaking experimentation focusing on materialsand the production process soon enabled him to improve the quality of glass production substantially. As such, increasingly larger lenses for telescopeswere being manufactured after 1811.A price list from this period shows awide range of products, coveringeverything from various types of tele-scopes through microscopes to mag -nifying glasses and opera glasses.

Fraunhofer’s increased involvement inthe management of the Optical Insti-tute gave rise to a rapid change in theproduct portfolio. The increasing quality of lenses paved the way for theproduction of higher quality optical instruments. A new price list publishedby the Optical Institute in 1812 flagsup a decided shift toward producingastronomical instruments.

This improvement in production tech -niques went hand in hand with Fraunhofer's empirical research. Initiallyhe focused on improving the imagequality of the lenses he manufactured.The lenses were a combination of aconvex lens made out of crown glassand a concave lens comprising flintglass with a lower refractive index.Both varieties of glass were producedin Benediktbeuern. The problem withcalculating these achromatic lenseswas knowing the exact refractive indexof the types of glass used in relation to the various colors in the spectrum.

Layout of the Benediktbeuernmonastery according to Benedikt-beuern land-registry records from 1811.


Growing success as a researcher

In April 1817, Fraunhofer submitted the first results of his research to the Royal Bavarian Academy of Sciences(now known as the Bavarian Academyof Sciences and Humanities) in Munichin the form of an essay entitled: “Be-stimmung des Brechungs- und Farben-zerstreuungs-Vermögens verschiedenerGlasarten in Bezug auf die Vervoll-kommnung achromatischer Fernröhre”(Determination of the refractive anddispersive indices of differing types ofglass in relation to the perfection ofachromatic telescopes). He reports thatmany years of experience had allowedhim to develop new methods for ascer-taining the diffraction and dispersionindices, and describes his methodology.He first experimented with prisms; he would alter the two refractive anglesby grinding until he suppressed thecolor dispersion and refraction. His in-tention was now to determine thecolor dispersion indices in each type ofglass. Fraunhofer stressed that numer-

ous tests had convinced him the linesand stripes he had discovered were an inherent property of sunlight andnot some random phenomenon. He counted 574 lines of various thick-nesses, which he drew and annexed to his Academy essay.

The discovery of these dark lines in thesolar spectrum, which were subse-quently named after him, enabled thediffraction indices of various types of lenses to be computed precisely, withFraunhofer achieving an astonishingdegree of accuracy for his results.

Various other test setups enabled himto determine the intensity of the spectrum colors and the diffraction indices of various pieces of glass. The quality of the molten glass meantit was now possible to compare varioustypes of lenses from the same melt.

Illustration of the solar spectrumdrawn and colored by Joseph vonFraunhofer with the dark linesnamed after him – testimony to the scientist's precise measure-ment techniques.


Fraunhofer impresses the scientificworld

The exposé for the Royal BavarianAcademy of Sciences in 1817 providedthe first high point in Fraunhofer’s scientific work. Through his researchand practical work in Benediktbeuernhe had gained a formidable scientificreputation. The court astronomer and director of the Munich Observatory,Johann Georg Soldner, for instance,wrote to the Academy, requestingFraunhofer be allowed into the Mathe-matics and Physics Section. In Febru-ary 1817, he was named a correspond-ing member.

Fraunhofer’s growing importance both in manufacturing high-quality optical instruments as well as in his research work in Benediktbeuern isalso reflected in contacts with leadingscientists of his day. In 1816, the Göttingen-based physicist Carl FriedrichGauß visited the Optical Institute inBenediktbeuern to place an order forinstruments for astronomical obser -vations. His verdict on Fraunhofer‘swork was glowing:“The Optical Insti-tute in Benediktbeuern is now it-self under the direct leadership of ahighly talented and energetic man, Fraunhofer, and supplies telescopes aswell as all astronomical instruments.”

Fraunhofer’s practical work changed in1819 when the Optical Institute movedto Munich. Back in 1814, Fraunhoferhad become Utzschneider's sole part-ner with the reorganization of the Mathematical-Mechanical and the Op-tical Institute. Financial difficulties forced Utzschneider to sell the exten-sive Benediktbeuern building complexto the Bavarian State in 1818.Utzschneider only held on to the glass-works; the idea was to keep providingglass to produce optical instruments.Fraunhofer also travelled regularly toBenedikt beuern to personally superviseeach glass melt and maintain the highstandards of quality.

On June 27, 1821, Joseph vonFraunhofer was appointed an extraordinary visiting memberof the Royal Bavarian Academyof Sciences.


The move to Munich now broughtFraunhofer into closer contact with the Royal Bavarian Academy ofSciences. After a series of internalacademy quarrels, partly the result ofFraunhofer’s lack of academic training,he became an extraordinary visitingmember of the Academy in 1821.

During this period he also examined various physical problems in a series ofessays and Academy speeches. He looked at the “causes of the tarnishingand matting of glass and means of preventing this” (“Ursachen des Anlau-fens und Mattwerdens des Glases unddie Mittel, demselben zuvorzukom-men”). Another piece of work involvedexperiments on the laws of light andphenomena produced by the movementof light.

Joseph von Fraunhofer demon-strates the spectrometer to Joseph von Utzschneider, Georgvon Reichenbach and GeorgMerz.


Epochal optical research: Fraunhofer in the limelight

Two of Fraunhofer’s groundbreakingpapers on light diffraction were published between 1821 and 1823.The first paper entitled “Neue Mo difi -kation des Lichts durch gegenseitigeEinwirkungen und Beugung der Strah-len, und Gesetze derselben” (Newmodification of light through reciprocal effects and diffraction of rays, and associated laws) was initially submittedto the Academy as a speech. In his second paper, Fraunhofer reported onhis new experiments on light wave theory. Diffraction needs to be seen asthe deviation of light dispersion fromthe laws of geometric optics; obstaclesimpair the straight line dispersion oflight waves. His papers on the diffrac-tion of light were an important pieceof basic research, which also hadrepercussions on the manufacture ofteles copes.

Fraunhofer describes his approach asfollows: He set up a screen with an adjustable aperture in front of the lensof a theodolite telescope. He then let the sunlight shine on the screen; thesunlight was diffracted by the aperture.“Through the telescope I could thenobserve the phenomena created by thediffraction of the light, enlarged, andyet with sufficient brightness, while atthe same time also being able to measure the deviation angles of thelight with the theodolite.”

As the next stage he investigated thereciprocal effects of a large number ofdiffracted rays and experimented with various means of diffracting light rays. Fraunhofer could now measureexperimentally the wavelength of all color light rays. He produced variousgrids with hitherto unsurpassed preci-sion in order to measure the diffractionspectrum.

His materials included glass in whichhe ruled a series of parallel lines, using a diamond to place them just0.00330 millimeters apart. The meas-ured wavelength values are extraordi-narily accurate, bearing in mind thetools available at the time. Fraunhoferused the lines he had discovered pre -viously in the color spectrum as part ofthese computations.

Joseph von Fraunhofer in hisworkshop.


Fraunhofer’s scientific reputation,which had been acquired not just onthe basis of these scholarly publi-cations, was also reflected in his per-sonal connections to importantEuropean researchers. In addition tothe aforementioned visit of Gauß to Benediktbeuern, other scientists werealso interested in forging links withFraunhofer.Visits to Benediktbeuern toplace orders for the renowned high-quality optical instruments provided anopportunity to talk to Fraunhofer. Forinstance, the scientists Karl Dietrichvon Münchow, Hans Christian Ørsted and John Frederic Herschel, son of the astronomer Wilhelm Herschel, all travelled to Benediktbeuern.

Visits to the Optical Institute by the political elite of the day also attest to the increasing importance of naturalsciences. Alongside Bavarian King Max I Joseph and his minister Count Montgelas, the Russian Czar Alexanderalso probably visited the research facilities in Benediktbeuern.

A leap in the quality of opticalinstruments

Under Fraunhofer’s direction, produc-tion had increasingly moved towardmanufacturing high-quality optical in-struments after 1811. The progressmade on the basis of Fraunhofer’spractical experience and his scientificresearch is manifested in the variousprice lists issued by the Optical Institute.In contrast to the modest beginnings, production switched to manufacturingtelescopes, trigonometrical measure-ment instruments and microscopes.The institute was a pioneer particularlyin the field of manufacturing lenses for telescopes. The diameter of telescope lenses increased from 83 mil-

limeters in 1813 to 245 millimeterswith the large refractor produced in1819 for the Russian Imperial Observa-tory in Dorpat. Plans even includedlenses measuring up to 490 millime-ters.

Utzschneider listed in his obituary theinstruments Fraunhofer had helped invent or improve. Among them were“the Heliometer, the multiple lamp filar micrometer, the achromatic micro-scope used to provide measurementsin absolute dimensions, the ring micro -meter, the lamp circle and network micrometer” and the aforementionedparallactic refractor for the Dorpat Observatory.

The theodolite (left) enables angles to be measured very precisely; the Heliostat (right) always directs the reflected sunlight to the same point so observations can be made irrespective of the earth’s rota-tion.


The difficulties that Fraunhofer had toovercome to manufacture this refractor– a unique instrument at the time – demonstrate the scientific standardsduring this period. In 1819, the lenswas the largest manufactured to date,with a focal length of 4.10 meters.

Distortion and possible temperaturedifferences had to be taken into account when fitting the lens. The pro-duction of the tube and the base took until 1824. Thanks to the paral-lactic mounting, Fraunhofer managedto follow a particular star simply by turning around a single axis. He alsodesigned a centrifugal regulator tomake it easier to track the telescope.

Fraunhofer’s publications in these years also confirm his substantial inputto this large astronomical instrument.He published two essays “on the con-struction of a large, recently completedrefractor” (“Über die Constructioneines grossen soeben vollendeten Re-fractors”) and examined astronomicalproblems, researching into phenom -ena such as sun dogs as well as solarand lunar corona.

High esteem – and an untimelydeath

Fraunhofer’s scientific acclaim grew asa result of the production of this refractor. In 1822, he was awarded anhonorary doctorate from the Univer-sity of Erlangen. A year later he wasappointed curator of the physics collec-tion of the Royal Bavarian Academy of Sciences. King Max I Joseph madehim a Knight of the Order of Civil Service of the Bavarian Crown in 1824,enabling him to join the ranks of thenobility. Various international scientificassociations also named Fraunhofer a member.

His personal circumstances, the grueling work in the glass furnaces,poisonous lead oxide and his frail physical constitution all probably con-tributed to Joseph von Fraunhofer's untimely death from “lung tuberculo-sis” on June 7, 1826, at the age of just 39. Fraunhofer’s gravestone in Munich bears the words “Approximavitsidera”: “He brought us closer to thestars.”

The honorary Knighthood of the Order of Civil Service of theBavarian Crown awarded on August 15, 1824 saw Joseph vonFraunhofer join the ranks of the nobility.


March 6, 1787 Joseph Fraunhofer is born, the eleventh child of Franz Xaver and Anna MariaFraunhofer in Straubing, Lower Bavaria.

1799–1804The young Fraunhofer completes an apprenticeship with the mirror maker anddecorative glass cutter Philipp Anton Weichselberger in Munich.

1801Weichselberger's house collapses; Fraunhofer is buried among the ruins. During the rescue work he comes into contact with the privy councilor Josephvon Utzschneider and prince-elector Maximilian IV Joseph.

1804–1806Fraunhofer works as an assistant to Weichselberger.

1806Fraunhofer becomes an optician at the Mathematical-Mechanical Institute run by Reichenbach, Utzschneider and Liebherr in Munich.

1808Fraunhofer works as a glass grinder in the Benediktbeuern glassworks, part ofthe Mathematical-Mechanical Institute; he publishes his first scholarly essay.

1809Apart from melting the glass, Fraunhofer is responsible for the entire glass production process in Benediktbeuern.

1811Fraunhofer takes over as overall head of the glassworks of the Mathematical-Mechanical Institute in Benediktbeuern.

1814Fraunhofer becomes Utzschneider’s sole partner and overall director of the Mathematical-Mechanical Institute.

Joseph von Fraunhofer.

Life

Joseph von Fraunhofer Time line


1817The Royal Bavarian Academy of Sciences names Fraunhofer a correspondingmember.

1819The Mathematical-Mechanical Institute moves to Munich.

1821After some heated debate surrounding his lack of academic training, Fraunhoferis appointed extraordinary visiting member of the Royal Bavarian Academy of Sciences.

1822University of Erlangen awards Fraunhofer an honorary doctorate.

1823Fraunhofer becomes titular professor and curator of the physics collection at the Royal Bavarian Academy of Sciences.

1824King Max I Joseph names Fraunhofer Knight of the Order of Civil Service of the Bavarian Crown, enabling him to join the ranks of the nobility.

7. Juni 1826Joseph von Fraunhofer dies in Munich.

Joseph von Fraunhofer next tohis spectrometer.


Dr. Josef Kirmeierrecounts the history of BenediktbeuernAbbey, its political and economic background, and the lifework of re-searcher and entrepreneur Joseph von Fraunhofer and of several impor-tant people he encountered.

Benediktbeuern Abbey secularizedand sold

All of the monasteries in Bavaria weredissolved in the years 1802 and 1803. This affected both the monaster-ies of the mendicant order, which were mostly situated in the towns, andthe rich abbeys of the rural orders. Atotal of 150 monasteries were secular-ized and taken over by the state. Theirvaluable books and works of art weretransferred to the state collections in Munich or were auctioned off. Eventhe monastery buildings themselves,and the land acquired by the ordersover what was often a thousand yearsof history, were sold to fill the statetreasury. This mortmain (“dead hand”)property, as the monastery assets werederogatively referred to at the time,was divided up and sold to private buy-ers or given to the monasteries’ occu-pants as compensation.

Benediktbeuern Abbey, one of the oldest monastic settlements in the Bay-erisches Oberland (Bavarian upperland) in Upper Bavaria, was also sub-jected to this wave of secularization. Its approximately 700 hectares of agri-cultural fields and meadows, some of which were in excellent condition,were distributed among more than150 buyers, most of them farmers fromthe surrounding area.

Research and productionGlassworks and Optical Institute in Benediktbeuern

The Optical

Benediktbeuern Abbey.


It proved rather more difficult to sell theactual monastery building itself. Thesame problem applied to other monas -teries, too. After all the rural cloistershad been abolished, there was a surplus of large properties on offer. Without their land, which had usuallybeen sold off, these properties couldbarely be managed. The huge buildingsthemselves were only marginally suitable for commercial use, and they were also hugely overpriced at first.

In the light of this situation, architectand Hofbaurat (royal privy councilor for buildings) Friedrich von Gärtnerconsidered tearing down Benediktbeu-ern Abbey to obtain building material for projects in Munich. The only reasonthis plan failed to materialize was because the transport costs would havebeen too high, and so Benediktbeuernwas spared the fate of WessobrunnAbbey, which was almost entirely pulled down and used to rebuild the fire-ravaged town of Weilheim.

It was not until 1804 and 1805 that interested buyers were found to purchase the abbey. After a failed take-over by Bohemian industrialistSchmaus von Stubenbach in 1804 anda refused offer of 78,000 guldens by Lucas, likewise an industrialist fromBohemia, the former Bavarian privycouncilor and entrepreneur Joseph vonUtzschneider made a proposal on May 3, 1805 to buy BenediktbeuernAbbey for 55,000 guldens. This sumwas finally accepted. The purchasecontract signed between Utzschneiderand the state of Bavaria covered a total of 28 items. In addition to themonastery itself – which included the library building, the hospital, thebrewery and the old parish church –Utzschneider acquired the alpine dairyfarm of Häusern, and various estatesand buildings that had formerly be-longed to the abbey. He cleverly took advantage of the fact that theseproperties were part of the unsold remains of the former abbey, and beatdown the price to even further belowthe offer originally made by Lucas. He went on to buy the steward’s house(“Maierhof”) in 1806 and a large partof the monastery forest north of theBenediktenwand mountains in theyears to follow. This increased his prop-erty to 2000 hectares, 1300 of whichwere forest, thus bringing it back tothe size of the former abbey.

The Historic Fraunhofer Glassworks with BenediktbeuernAbbey in the background.

Institute


Utzschneider’s plan: glassmaking

Utzschneider’s purchase was motivatednot only by plans to continue farmingthe monastery’s land but also to set up a glassworks in the abbey. At firstglance, the interest displayed by thetwo Bohemian glassmakers in the prop-erty, and Utzschneider’s intention of establishing a glass factory on site, appear to be explained by the presenceof silica sand and wood nearby. How-ever, most of the woodlands requiredfor melting glass had already been soldoff elsewhere and had to be boughtback – which is exactly what Utzschnei-der did. The most important resource,silica sand, was to be found in a placecalled Quarzbichel, just south of Wolfratshausen. But both the sand andthe wood could easily have been transported to another site.

The main reason behind this interest is therefore more likely to have beenthe reduced price of the abbey’s “remaining stock” and perhaps alsothe proximity to Tyrol, which was apromising sales market for glass. Tyrolhad no glass production of its own, but had a traditionally high demandfor the material.

Glass and politics

What will remain unclear is to what extent Utzschneider sensed that Tyrol would be ceded to Bavaria in De-cember 1805 when he made his offerin May of the same year, and that this separation from Austria would alsocut it off from the Bohemian glass market. This decision, made in the con-text of the Peace of Pressburg, meantthat the sales market of Tyrol was sud denly accessible to Bavarian glassproducts without any border restric-tions or competition.

Utzschneider’s decision to buy theabbey could thus have been swayedlargely by the opportunity to producecheap consumer glassware, rather than the high-quality optical glass thatbecame important later on. It was notuntil the sudden loss of Tyrol followingthe fight for freedom led by AndreasHofer that the glassware productiontapered off and eventually ceased. Theglassworks for these products, whichwas located in a detached building onthe west side of the monastery, wastorn down in 1843. At the same time,the production of optical glass becameincreasingly important, mainly thanksto the accomplishments of JosephFraunhofer. The factory for opticalglass remained in operation until 1887,and is still largely intact today.

Inside view of the glassworks inBenediktbeuern, where Josephvon Fraunhofer tested newmethods of producing high-qual-ity glass.


Utzschneider had temporarily left hispost as a civil servant in 1801, althoughhe continued to receive his salary, and had immediately embarked on anumber of private-sector activities, establishing himself as one of the firstindustrial entrepreneurs in Bavaria. He founded a leather goods factory ina former Carmelite monastery in Munich in 1802 which, together withits affiliated glue factory, soon counted170 employees and was thus one of the largest industrial enterprises inMunich.

His interest in glassmaking and opticshad accrued from his participation inthe Mathematical-Mechanical Institutefounded by Georg von Reichenbachand Joseph Liebherr in Munich in 1804.Reichenbach and Liebherr, who weremanufacturing astronomical devicesand measurement instruments basedon the circle-dividing machine deve l -oped by Reichenbach, found Utzschnei-der to be a strong partner with plentyof capital and willing to take risks. He equipped the institute with the nec-essary funds and facilities, and alsotook charge of selling its products.

The goal: to make quality glass forprecision instruments

Utzschneider’s goal was to remedy thelack of high-quality glass which hadhitherto greatly hindered the productionof optical devices. Optical precision in-struments could only be manufacturedusing an ingenious combination offaultless crown and flint glass, each ofwhich has different refraction and dispersion characteristics. There wassimply no other way of producingpowerful optical devices with a relativelyhigh rate of magnification. The glasseshad to be homogeneous, i.e. free of streaks and bubbles, in order to beused in optical devices. Until the beginning of the 19th century, theyhad been produced exclusively by twoEnglish glassworks, which were unable to supply sufficient quantitiesand often only delivered mediocrequality.

For this reason, Utzschneider had at-tempted to produce the glasses himselfeven before Napoleon’s Continental System came into effect in 1806. How-ever, his first experiments in the glass-works at Grafenaschau – originally partof Ettal Abbey, into which Utzschnei-der’s sister had married – failed. His acquisition of the monastery in Benedik tbeuern, and the constructionof a glassworks there, filled him withfresh hope.

Georg von Reichenbach was co-founder and associate of theMathematical-Mechanical Institute, which was joined byoptics expert Fraunhofer in 1806.


Stirring process brings first successes

In searching for a suitable expert, Utzschneider traveled to Les Brenets inSwitzerland, where he met Pierre LouisGuinand. Guinand had been producinghigh-quality glass for a good manyyears, and Utzschneider managed torecruit him for Benediktbeuern for ahigh wage of 1600 guldens.

The first melting trials at Benedikt-beuern took place in January 1806. Ini-tially, the resulting glass was of varyingquality, but a suitably adapted stirringprocess derived from the bell-foundingtechnique put Guinand on the righttrack to producing purer glass. Theproblems encountered in glass meltingwere attributable to the insufficienttemperatures achieved by the fuels andfurnaces available at the time. Thewood-fired furnaces were barely capa-ble of generating the 1300 degreesCelsius needed to melt the glass, let alone the 1500 degrees used today,

and this meant that the glass lackedthe required homogeneity. Guinandthen attempted to compensate for thisshortfall by inserting a stirring deviceinto the glass melt in his self-developedfurnace. This device thoroughly stirredthe mass once the glass becamemolten in the sealed furnace. The stir-ring arm, which was equipped withfire-proof clay and could be swungover the furnace and lowered into themelt, can still be seen at the glass-works today.

The stirring process developed by Guinand and enhanced byFraunhofer contributed signifi-cantly towards improving thequality of the glass. The pictureshows a cross-section throughthe furnace and the stirring de-vice.


The new technique employed in Bene -diktbeuern made it possible to produceabout 20 kilograms of glass in onemelting cycle,which took several weeks.As soon as the glass had cooled off enough, it was lifted out of the furnace and subjected to a quality inspection. Parts that were suitable forfurther processing were placed in a specially designed furnace to cooldown slowly, so that they would set without any tension. The plants andfurnaces on display at the glassworkstoday are from a later date but alsoworked according to Guinand’s prin -ciple.

The process was further developed byGuinand and later by Fraunhofer, leading to the highest-quality specialglass of its time for optical devices. Initially, the glass was processed exclu-sively by the Mathematical-MechanicalInstitute in Munich, but an increasingnumber of optical devices were alsomanufactured at Benediktbeuern afterFraunhofer joined the venture.

Guinand takes his know-how backto Switzerland

The initially clear division of tasks be-tween Munich, Benediktbeuern and the company’s associates became moreand more blurred over time, which led to a number of difficulties and eventually changes in staff. In 1807 Utzschneider integrated the Benedikt-beuern glassworks, which had oper-ated independently until then, into the Mathematical-Mechanical Instituteso that only this enterprise would benefit from the glass produced.

Polishing dishes from Fraunhofer’sfactory.

Fraunhofer carried out severalseries of systematic tests to de-velop new types of optical glass.The picture shows a pentaprismproduced by him.


The decision to shift part of the pro-cessing to Benediktbeuern turned out to have serious consequences.Guinand failed to achieve the desiredsuccess as head of the Optical Institute,so Utzschneider handed the respon si -bility for this part of production inBenediktbeuern over to Joseph vonFraunhofer. Guinand, who had workedentirely independently until then, felt discriminated by this decision andby the competition he saw in Fraunhofer. The situation escalated

even further in 1811, when Fraunhoferwas appointed head of the entireBenediktbeuern company, and thus became Guinand’s superior. This made it impossible for the two to work to-gether, so Guinand decided to leavethe glassworks in 1814, and returnedto Switzerland.

Guinand took his newly acquired know-how on glass production and processingfrom Benediktbeuern to Switzerland,where he brought his former glassworksin Les Brenets up to the latest standardsand significantly contributed to pro-moting glass production in Switzerlandand France. Utzschneider’s attempts at binding Guinand to the company bypaying him a pension, failed.

Gear milling machine fromFraunhofer’s glassworks.


The company is reorganized anddivided

However, there was also an increasingamount of tension between the company’s associates in Munich, notleast as a result of the expanded production in Benediktbeuern. Liebherrand Reichenbach had little interest inexpanding their institute, as they were not industrial entrepreneurs butrather saw their work as a form of arts and crafts. This was accompaniedby the special situation in which Utz schneider, through his financialcommitment to Benediktbeuern, increasingly took charge of how thecompany was managed. Because the substantial investments made inthe Benediktbeuern glassworks had not yet paid off in the short spaceof time since its foundation, Utz -schneider invested another 60,000guldens out of his own pocket in addition to the Munich institute’s con-tri bution of 12,000 guldens. Thistrans action, and the shift of part of theoptical processing to Benediktbeuern,was bound to make the other partnersfeel alienated.

These differences in opinion and per -haps also mentality between Utz -schneider, Reichenbach and Liebherreventually drove Liebherr to tem -porarily leave the Munich institute in 1812, and caused Utzschneider andReichenbach to go their separate waysin 1814. While Liebherr’s decision to leave was most likely swayed by dis-putes with Reichenbach concerning Liebherr’s share in the invention of thecircle-dividing machine, it also emerges from various statements thatneither of them wished to supportUtzschneider’s risk-friendly, market-driven management policy any longer.Reichenbach’s main accusation wasthat the Benediktbeuern company wasuseless and had produced nothing but losses from 1809 to 1814, whereasthe Mathematical-Mechanical Institutein Munich had achieved a profit of 100,000 guldens over the same period.

Top:Raw glass block produced in amelting process at the glassworksin Benediktbeuern.Bottom:Cross-section through a filledmelting crucible.


The discord between Utzschneider andReichenbach led to the separation ofthe Munich and Benediktbeuern enter-prises in 1814. Reichenbach carried on the Munich institute together witha mechanic called Traugott LeberechtErtel, initially under the name of Math-ematical-Mechanical Institute of Reichenbach and then Mathematical-Mechanical Institute of Reichenbachand Ertel from 1815 onwards.Utzschneider immediately founded acompeting enterprise, which wasjoined by Reichenbach’s former partnerLiebherr and tradesman C. l. Werner.The glassworks at Benediktbeuernacted as an independent supplier andwas not integrated into the new insti-tute. Joseph Fraunhofer was given a 10,000-gulden share in the enterprise.However, he was not entitled to withdraw this sum from the company’s equity. Former partner Reichenbachcontinued to be supplied with glassfrom Benediktbeuern, but was not granted any special conditions.

Despite the allegedly difficult financialsituation of the Benediktbeuern company and the changes taking place in the organization, it evolved into a distinguished enterprise with a staff of 48 in just a few years. Twenty glass grinders, five turners, two tubedrawers, two wheel drivers, a caster,an optician, a stoker, two girdlers andfourteen other workers were employedthere. According to a state survey, they generated a production value ofapproximately 50,000 guldens, al-though this sum almost certainly includes the revenues of the consumerglassware factory. Company documentsreveal that 95 large melting processestook place in Benediktbeuern between 1811 and 1825. The resulting yield of usable flint and crown glass stood at 30 percent and comprised atotal volume of 6000 kilograms.

Prisms were used to examine thequality of the glass.


Fraunhofer focuses on quality

When Joseph Fraunhofer became manager of the company, he focusedthe production even more strongly on high-quality scientific glasses. Themanufacture of consumer glasswaretook a back seat and was eventuallyabandoned. The optical products madefrom Benediktbeuern glass were deemed to be of unparalleled qualitythroughout Europe.

The precondition for such quality wasto use absolutely pure glass, and this was made possible by the stirring method developed by Guinand. Thiswas Guinand’s major contribution to the production of optical glass. How-ever, the essential innovations thatmade the Benediktbeuern glass so valuable can largely be ascribed toJoseph Fraunhofer and his scientificworking approach. Guinand was anadept craftsman, who sometimesmade progress almost coincidentally bytrial and error. Fraunhofer, by con -trast, took a much more goal-oriented,systematic and ultimately more suc-cessful approach. He started by select-ing suitable raw materials, and setgreat store by their purity. He did notuse the sand from Quarzbichel, for example, but had silica brought overfrom Tyrol. After significantly improv -ing the purity of the raw materials employed, he determined the best mix-ture in a series of tests.

Fraunhofer’s work soon bore fruit. TheBenediktbeuern glass made it possibleto produce larger and larger lensesthat attracted customers not only inBavaria but throughout Europe. Themain secret behind these large lenseswas an improved melting processachieved by Fraunhofer in collabora-tion with Guinand. In this “sinking”or“bending” process, a finished glassmass was re-heated until it could bemolded into the negative shape of a lens. This blank was then ground andpolished.

Left:Multilayer prism.Below:Equilateral prisms in different colors.


Telescopes establish the good reputation of Fraunhofer and Benediktbeuern

Other achievements by Fraunhofer include his method of evaluating theglass produced, his improved process-ing methods involving his grinding machine, and his techniques for trans-forming the glass into optical devicesthat were of particular importance to astronomy. On the basis of hisknow ledge about the refractive behav-ior of light and his exceptionally ac -curate calculation methods, Fraunhoferwas able to build achromatic tele-scopes with lens apertures of 25 cen-timeters, which had been deemedimpossible until then. These telescopescontinued to dominate the astron -omy scene for half a century, and the

glassworks at Benediktbeuern becamerenowned even far beyond the Bavar-ian borders. Many of the major obser-vatories in Europe were equipped withinstruments from the Utzschneider-Fraunhofer business.

The reason why Fraunhofer’s researchon refractive behavior was so im -portant becomes evident on taking acloser look at the operating principlebehind the achromatic telescopes. Thebasic problem in producing telescopesis that white light is refracted differ-ently after passing through a glassprism. This phenomenon, known asdispersion, made it impossible to buildrefracting telescopes with more than30-fold magnification, as the colorshift occurring at higher magnificationlevels rendered the results useless.Achromatic telescopes make use of thefact that different types of glass have

Three-tiered telescope bearingthe inscription “Utzschneider,Reichenbach und Fraunhofer inBenediktbeurn”.


different degrees of refraction. Thecrown glass mentioned earlier on barelyrefracts the light at all, while flint glass refracts it to a very strong degree.The idea behind achromatic telescopeswas to offset the dispersion of light by lining up the different glasses along-side one another. Earlier attemptsmade without this knowledge aboutthe behavior of light only succeededoccasionally by chance and were limited to a certain size of telescope.Fraunhofer’s great achievement wasthat he recognized the physics behindit and developed precise measuringtechniques that were of crucial impor-tance to the composition of the lenses.This explains the leading role played by the Benediktbeuern glassworks andthe optical devices developed underFraunhofer’s auspices.

Production recipe for quality glass is revealed

The composition of raw materials spec-ified by Fraunhofer for making flintand crown glass was top secret. In ad-dition to silica sand, the most impor-tant materials for the weakly refractingcrown glass were alkaline salts, silicicacid and lime, while the strongly re-fracting flint glass produced in the sec-ond furnace was made using lead inplace of lime.

However, the recipe could not be kept secret in the long run, as the lead-ing position of Utzschneider’s companyrested on Fraunhofer’s skills and re-search findings, which Fraunhofer him-self published and made accessible.Then, after Guinand and other workersleft Benediktbeuern, the operatingprinciple of the furnace and the approximate composition of the glassbecame known much further afield.The same was true for the sinkingprocess, which Guinand had helped todevelop, or, as his correspondence indicates, about which he possesseddetailed information.

Above:Lenses produced in Benedikt-beuern.Below:Small watchmaker’s lathe on avise from Fraunhofer’s glass-works.


Benediktbeuern becomes state-owned once again

The financial returns of the optical enterprises were limited, even when thebusiness was doing well. The institutein Munich and the glassworks inBenediktbeuern could not decisivelyremedy Utzschneider’s tight financialsituation in the long run. Utzschnei-der’s widely ramified enterprises which,in addition to the optical businesses,included the previously mentionedleather goods factory, a cloth mill anda brewery, were highly indebted. The ambitious entrepreneur, who hadmoreover resumed his work as a civil servant in 1807, had clearly over-reached himself. After a failed attemptat securing state funding for parts of

his businesses – especially for the glass-works, which were also of strategicand political importance to the king-dom – Utzschneider felt impelled to sell Benediktbeuern Abbey in 1818.

In January that year, he offered the kinghis estate for an overall sum of362,587 guldens. As early as March,Utzschneider reached an agreementwith the Bavarian state, and sold the property for 250,000 guldens. Theformer monastery of Benediktbeuernwas used to breed military horses, following the destiny of the originallyelector-owned estates of Schwaigangerand Schleißheim and the secularizedmonasteries of Fürstenfeld and Steingaden. The former alpine monasticsettlements of Straßberg and Wallwere also bought up by the Bavarianarmy. At the beginning of the FirstWorld War, the formerly monastic in-dustrial complex comprised 2600hectares of property with 800 horsesand 100 cattle, and was Bavaria’slargest Remontedepot, as such foal-rais-ing estates were called. The consumerglassware factory was sold togetherwith the monastery and, since no inter-ested buyer was found, it continued to be run by the Bavarian army until itsproduction was ceased.

Fraunhofer’s telescopes wererenowned for their excellentquality, which helped the entre-preneur to become as successfulas he was.


Fraunhofer’s successor at the glassworks

The factory’s optical glass productioninitially remained unaffected by thesale of the monastery. Under the tech-nical direction of Fraunhofer, theBenediktbeuern glassworks was able to maintain its position on the market.And the two optical institutes in Munich and Benediktbeuern were, afterall, among the healthiest and mostprofitable companies set up by Utz -schneider, whose widely ramified activ-ities had led many people to doubt his solidity. It was not until Fraunhofer’spremature death that Utzschneider’soptical businesses, too, plunged into acrisis. Friedrich August von Pauli,whom Fraunhofer had favored as hissuccessor, did not take up the chal-lenge and so, after failed negotiationswith C. A. Steinheil, Utz schneider re-placed him with Georg Merz, who had already been working in Benedikt-beuern for 18 years. Merz was supported by Joseph Mahler, who wasappointed head of pro cessing opera-tions.

The years following Fraunhofer’s deathwere dedicated to finishing the tasksthat had been taken over from him –tasks which his successors did their bestto fulfill. Because the two practitionershad limited theoretical knowledge,they occasionally sought the advice of astronomer Thomas Clausen. Merz did not appear to have gained Utz -schnei der’s full trust from the outset,being denied access to work on the glass melting process, which waskept strictly secret for a long time. It was not until 1832, six years afterFraunhofer’s death, that Merz tookover this task. In 1839, Merz andMahler finally bought the Benedikt-beuern glassworks and the Munich in-stitute from the then 76-year-oldUtzschneider, and named the business“Merz & Mahler”. Joseph von Utz -schneider died in 1840.

The production in Benediktbeuern wascarried on until 1883, and the factorycontinued to produce optical glassesunder the direction of Georg Merz’ssons. The glassworks was eventuallydecommissioned, not only in the faceof competition – particularly that from Bohemia, which had long sincecaught up with the technologies ofGuinand and Fraunhofer that had orig-inally given the business a head start –but ultimately due to the Bavarian for-est administration, which refused totolerate the ongoing depletion of theBavarian army’s forest lands any longer.

Left:Fraunhofer as portrayed a fewmonths before his death.Below:The two melting furnaces at theglassworks in Benediktbeuern.


Pater Prof. Dr. Dr. Leo Weberdescribes and documents the history ofthe glassworks and the Optical Insti-tute at Benediktbeuern in the days ofJoseph von Fraunhofer.

Joseph von Utzschneider purchasesthe monastery complex in Benedikt-beuern

Joseph von Utzschneider applied topurchase the buildings of the formermonastery in Benediktbeuern in May1805.1 He was planning to establish amodern “optical institute” there. Themonastery buildings were “extradited”to him on July 6, 1805. Various docu-ments dating from September 17, October 8 and November 4, 1805, des-ignate him as the “owner of the localdissolved monastery”, namely Benedikt -beuern.2

In 1805 Utzschneider had taken pos-session of most of the monasterybuildings, but not the steward’s house(“Maierhof”). The bill of sale is datedOctober 23, 1807.3 A distinction mustbe made between the purchase andthe bill of sale. This was the case whenUtzschneider sold the monastery com-plex to the king of Bavaria. The build-ings were handed over on February 15,1818 as customary after a sale, but the bill of sale concerning this transac-tion is dated March 2, 1818.4

The bill of sale dated October 23, 1807 assumes inclusion of the barrel-maker’s shop, the wainwright’s shop,the smithy and the brewery cooperage.These buildings were erected before 1803.5 The sum quoted in the bill ofsale is 58,150 guldens.

Joseph von Utzschneider and Joseph von Fraunhoferat the former Benedictine monastery of Benediktbeuern, 1805–1818

Benediktbeuern Abbey.

Utzschneider


The former monastic washhouse nextto the millstream at the south-easterncorner of the monastery complex,which actually bridged the stream, andthe large four-wing steward’s house in the north-east of the complex are notincluded in this bill of sale. Joseph von Utzschneider purchased these sep -arately from the other buildings. He bought the monastery washhouseas early as October 8, 1805, paying a price of 450 guldens to its residentAnastasia Herzlin, the widow of a tea cher. Mrs. Herzlin was moreover gran ted life tenancy free of charge in the nearby village of Häusern.6

The large “former monastery steward’shouse”, an extensive four-wing edi fice in the north-eastern part of themonastery complex, had originallybeen purchased by Johann Georg JosephFuchs of Munich “from the royal localadministration commission in Benedikt-beuern” on January 20, 1804.7 Fuchswas the treasurer of the “royal andrural joint debt-settlement commission”in Munich. As “royal privy councilor”,Joseph von Utzschneider purchased themonastery steward’s house from treasurer Fuchs for 26,000 guldens onSeptember 18, 1806.8 The property did not pass to Utzschneider in 1805,as some accounts still claim. His

starting investment of 58,150 guldensfor the monastery complex thus increases by at least the 450 guldensfor the erstwhile washhouse and the26,000 guldens for the steward’shouse to a total of 84,600 guldens. Hisexpenses rose even higher through various minor additional payments andthrough buying back former monasterylands which had been auctioned offduring secularization.

Joseph von Utzschneider intended toset up a model agricultural business inthe former Benediktbeuern monastery,which is why he also wanted to purchase the steward’s house.9 He wasalso very keen to reunite the proper -ties and fields that had been “torn apart”by the secularization.10

As of 1807, “the alpine dairy farmknown as Häusern”, east of Laingruben– since 1865 the village of Benedikt-beuern –, once again became part ofthe estate, i.e. the totality of the origi-nal monastery complex. The Bavariangovernment had meanwhile sold it tothe Mennonites, as no other purchasercould be found. It is probable that Utzschneider continued to cultivate themonastery garden. Nevertheless, heused one of the greenhouses to set uphis optical instruments.11 He activelycampaigned for the reclamation ofmarshy ground. Two marshy areas to-taling 708 Tagwerk (about 62 acres)were assigned to him “for cultivation”.He drained them as he had done withother areas.12 Today we count it as progress to waterlog these areas onceagain.

The marked window of thehouse adjacent to the glassworkswas probably the location of thesix lamps with which Fraunhofercarried out experiments on therefraction of glass for light ofdifferent wavelengths over a dis-tance of precisely 225 meters.

and Fraunhofer


The establishment of the OpticalInstitute and Fraunhofer’s livingquarters

Joseph von Utzschneider deliberatelyplanned to keep together and maintainthe buildings of BenediktbeuernAbbey, which had been dissolved inthe 1803 secularization movement, by giving them a new meaning and pur -pose – in itself a great service to thehistory and culture of Bavaria, specifi-cally Benediktbeuern. The most impor-tant facility in the former monastery of Benediktbeuern is the “Optical Insti-tute”, which he founded jointly with Joseph Liebherr and Georg vonReichenbach in 1805/06 as a branch ofthe institute in Munich.13 Its objectivewas to meet the need for optical meas-uring instruments for the planned land survey, but also to provide betteroptical devices for everyday use, suchas telescopes and microscopes.

This required top-quality “optical”glass. Formerly called ripple-free flintglass, it is known today as “non-stri-ated” or “homogeneous” glass. Onlywith glass quality of this kind could any success be achieved in the highlysensitive optical industry. To beginwith, Utzschneider planned a meltingfacility with large, and permanently installed melting furnaces. This was setup next to the former washhouse ofBenediktbeuern Abbey, not inside thewashhouse, as older literature repeat-edly asserts.

Crown glass and flint glass were to bemelted in these large furnaces. The latter had a stronger coefficient of re-fraction. Its glass melt contained lead.It has recently been surmised thatJoseph von Fraunhofer contracted leadpoisoning through handling these materials.

The newly built glassworks is known inthe literary sources as the “harborworkshop” or “glass furnace works”with “2 optical glass furnaces” and an“iron secondary furnace”.14 There was also a “large walled-in boiler”. The“optical glass grinding shop”, on theother hand, was accommodated in theformer washhouse next-door. This was also called the “optical factorybuild ing”. At ground level it had “6 small workshops with a waterwheel”,and on the upper story, where theglass was ground, it had 5 rooms and 1 kitchen.15 Joseph von Fraunhofer wasthe first person to direct this “glassgrinding shop”.

A clear distinction was made betweenthe “washhouse” and the new “glassfurnace works” directly adjacent to it.Against the garden wall behind thisglassworks was a “Dari furnace con-taining iron doors and rods, ... likewisethe sandworks in front of and behindthe house down to the stream”.

Soon after the “optical glassworks”Utzschneider founded a “commonglassworks” for normal consumer glass-ware.16 Its building was located to the west of the west wing, about 80 to100 meters distant, on the central axisof the monastery complex.17

The Swiss scientist Pierre Louis Guinandhad invented the new stirring methodused at the glassworks, and JosephFraunhofer improved this method. Hewas the first person to succeed in pro-ducing a homogeneous glass quality;he also created lenses with a muchlarger diameter than ever before, evenlarger than those from the best produc-tion facilities in England. After PierreGuinand had left, Joseph von Fraunhoferalso assumed responsibility for themelting process and thus for the entireglassworks.

Joseph von Fraunhofer revolu-tionized the production of high-quality glass.


A few years later, he also became headof “Optical Mechanics” and director ofthe entire“Optical Institute”in Benedikt-beuern. Fraunhofer achieved his trail-blazing successes during his activities in Benediktbeuern from 1809 to 1819,causing the former Benedictine mon-astery of Benediktbeuern to become aworld leader in the optical industry.Thanks to the quality of his glass, hissmall and large lenses and prisms, andhis method of grinding and polishingthe lenses and assembling the opticalinstruments, Fraunhofer rose to the fore-front of the industry. In addition, hecarried out research on the behavior oflight using his best optical glasses andgained completely new insights in thisarea, too. In return, he was made amember of the aristocracy, adding“von” to his name to become Josephvon Fraunhofer.

His most important discovery is the“Fraunhofer lines”, a set of spectrallines in the spectrum of the sun’s lightthat are named after him. This markedthe start of spectral analysis, whichplays an important role in the investiga-

tion of the universe to this very day.Benediktbeuern became the “cradle of scientific glass technology”.18

It is therefore all the more interestingto know exactly where and in whichrooms Fraunhofer lived, worked andstudied, where he was at home. Astone plaque which King Ludwig I ofBavaria had hung above a door in thewall in the corridor of the Fürstenflügel(“prince’s wing”) on the upper story in 1841, fifteen years after Fraunhofer’spremature death, provided a first clue: “Joseph von Fraunhofer, inventorof ripple-free flint glass, worked herefrom 1809 to 1819”.

Joseph Fraunhofer came to Benedikt-beuern in about 1808/09.19 Probablyfrom 1809 onwards, he lived in the first five rooms of the outer south wing,which is known today as the Fürsten-flügel or Fürstentrakt, starting from thewest end of the long corridor in theupper story as far as the “great hall”,the Kurfürstensaal, which today servesas a house chapel for the Salesians of Don Bosco. It was used as a “hall ofoptical instruments”.20

In the list of rooms drawn up in 1818,the description of No. 145, immedi-ately after the door in the corridorfrom the west wing to the south wing,the “new building” or “summerabbey”, today’s Fürstentrakt, runs asfollows: “Kitchen, contains a cast-ironwash boiler and a copper boiler”, the property of Mr. Fraunhofer. This isfollowed by room numbers 146, 147, 148, 149. These are described as “Mr.Fraunhofer’s living quarters”. They are immediately followed by No.150,the “great hall”, or the “hall of optical instruments”. This room couldnot be heated. Joseph Fraunhofer’s immediate living and study areas arethus clearly identified. This is where he lived, studied and carried out exper-iments with the optical instruments in the great hall directly next-door – butprobably not the light experiment with the six light sources. The distancefrom the target building was too shortfor this, and moreover there was nounobstructed view.21 But it was essen-tially Fraunhofer’s domain. It was probably in these rooms that he discov-ered the “Fraunhofer lines” in thespectrum of the sunlight, which werelater named after him.

Fraunhofer also designed micro-scopes with outstanding opticalproperties.


The “great hall” (Kurfürstensaal), withits high windows on the east, southand west sides, turned out to be the hall of spectral colored sunlight dis-plays, as the writer of this text hasbeen privileged to observe many timesat sunrise. In spring, when the weatheris good, the incident sun beams penetrating the window glass from theEast cause fields of light with the clearspectral colors of red, orange, yellow,green, blue and violet to occur at shortintervals one after the other, and tocreep across the floor, between chairlegs, and up the inner north and westwalls of the hall. Fraunhofer, too, must have experienced these coloredlight fields, as he often spent time inthis hall experimenting with the opticalinstruments. It is almost certainly thisdisplay, and not just his experiencewith a feather in the monastery tavern,that inspired him to further investigatethe phenomenon and led him to discover the numerous absorption linesin the sun’s rays.

Because of Fraunhofer’s success in glass technology and science, theserooms associated with his personal life are of greatest historical importance.

A narrow spiral staircase led down -wards from the kitchen (Nr. 145) to theground floor.22 Possibly its purpose was to provide the researcher with ashort cut to the workshops for “Op-tics” and “Mechanics” in the front partof the eastern ground floor. In front of the “great hall”, however, was the“master staircase”, known today asthe Fürstentreppe (“prince’s stairs”). Itwas via these stairs that the optical instruments were transported into the“great hall”.

Spectral prism device from Fraunhofer’s workshop. Such de-vices were used to separate the incident light into differentwavelengths.


The rooms on the ground floor of the“new building” were not as elabo-rately equipped as those on the upperfloor. They were suitable for use as precision engineering workshops forthe manufacture of optical instruments.Lathes and joining benches, machinesfor the “mechanical workshop”, later to become the “mathematical-mechanical-optical institute”, were installed and used here. Five rooms onthe ground floor, numbered 82, 83,84, 85 and 86, were set aside for thesemachines, starting at the eastern endof the building and extending as far as

the stairs to the basement and the“main stairs” to the upper story. Theyconstituted the third area of the Optical Institute in the former Benedikt-beuern monastery.

The fourth set of rooms were Fraunhofer’s own living quarters andstudy rooms. These represent the“think tank” of the entire complex. Itwas from here that the decisive andprogressive impulses, the innovations,emanated. The rooms in the third area,the mathematical-mechanical-opticalworkshops, were likewise rented forthe Optical Institute, which continuedto exist when the monastery complexwas sold to the Bavarian king.

The first area of the Optical Instituteconsisted of the “harbor works”, andthe second area was the “glass grinding shop” in the former wash-house immediately adjacent to the harbor works. All three areas were ulti-mately under the control of Joseph von Fraunhofer. In 1817 the as-tronomer Johann Georg von Soldner,who was a friend of Fraunhofer’s, organized for him to become a mem-ber of the Royal Bavarian Academy of Sciences. He described him as “thebest practical optician alive”, who atthe same time was an excellent “theo-retical optician and experimenter”.Soldner also noted that: “He has allthe resources one could possibly wantat his disposal; he has an admirableworkshop in which he himself has builtall the devices that he requires; hemixes and melts his glasses just as heneeds them, and grinds them to hisown calculation.”23

The 9-inch refractor in theDeutsches Museum was built toFraunhofer’s plans.


Supplementary notes

A “six-year-old brown saddle-horse; a one-wheel yellow Swiss cart; a rope-pulled sled; an oat-bin” are listed as“the property of optician Jos. Fraunhofer” in 1818. They were lo-cated in the “Oeconomie”, i.e. on the premises of the stables that werecontrolled by the steward’s house.24

Even after the “mathematical-mechani-cal-optical institute” had been relo-cated to Munich in 1819, Joseph vonFraunhofer frequently returned toBenediktbeuern to supervise the glassmelts. It is likely that he lived in therooms described until his prematuredeath in 1826.

1818, Utzschneider kept on numerousrooms on a rental basis, as he wantedto continue with the manufacture ofboth optical glass and normal glass.Glass was melted at the “optical glass-works” until about 1887.25 SigmundRitter von Merz, the son of GeorgMerz von Bichl, continued the practice.

On the ground floor of the erstwhilemonastery “hospital”, also known asthe “pharmacy”, between the formerwashhouse and the “new building”,there were two rooms “containing furnaces for casting and mold dryingbelonging to the Optical Institute”. The glass grinders had their bedroomsand living quarters on that sameground floor, and the “individuals formechanics and optics” were one storyabove them. Five further “bedroomsand living quarters for mechanics”were located in the convent building. Itis probable that the family of GeorgMerz von Bichl, Joseph von Fraunhofer’sfirst associate, also lived there.26

A “large-scale lens radius grinding machine” was walled into the groundfloor of the library building. The“upper part of the large-scale radiusgrinding machine” was accommodatedin the “room” above it, the formermonastic archive. Nailed to the ceilingwere “a large pulley” and “a small ...hoisting frame”, as well as the “frameof the large roller-burnishing ma-chine”. “Under the roof” of the library– presumably reached from the attic –there was “a large elevator” to thelarge-scale radius grinding machine. Allthese instruments and machines werethe “property of the Optical Institute”and were not sold on February 15,1818. They remained in the hands ofJoseph von Utzschneider.27


Sources in German

1 BayHStAM IV, Kriegsarchiv, M Kr 14 953 Remontedepot Benediktbeuern Bund 1, 1806 –1822. Kaufvertrag vom 23. Oktober 1807, XX.

2 A. a. O. Bund 1.3 Wie Anm.1. – Vgl. Bayern und seine Armee.

Eine Ausstellung des Bayerischen Haupt-staatsarchivs aus den Beständen des Kriegs-archivs (Ausstellung und Katalog: Rainer Braun in Zusammenarb. m. Gerhard Heyl / Andrea Groß; Red.: Albrecht Liess; 9. Juli – 30. August 1987), München 1987, 300, Nr. 163.

4 Wie Anm. 1, Unterkonvolut IV.5 So auch das Gutachten von Baufachmann

Strehler 2005. 6 Wie Anm. 2.7 Ebd.8 Ebd.9 Günter D. Roth, Joseph von Fraunhofer.

Handwerker, Forscher, Akademiemitglied 1787–1826 [= Große Naturforscher 39], Stuttgart 1976, 70.

10 KAM, A XIX b.1. Remontierung Benedikt-beuern – Kap. IV, Lit. Benediktbeuern Nr. 1.Militär-Fohlenhof Benedictbeuern. Ankaufdes ehem. Klosters vom Jahre 1818 bis 1822.Fasc. III ( NB.: Auf dem Innendeckel heißt es:»1818–1821, Fasc. II«). 3. Konvolut, 25. Jänner 1818 (Jos. Utzschneider an KönigMaximilian I.; eigenhändig), eingelegt imProdukt v. 6.II.1818. – Vgl. Bayern und seineArmee (wie Anm. 3), 297.

11 Wie Anm. 10, 1. Konvolut, Unternummer 5 ad 87. – »Das alte Treibhaus im Hofgarten« war »zur Aufstellung eines großen Fernrohrsbestimmt«.

12 Wie Anm. 10, 1. Konvolut, Unternummer 38. – Vgl. Bayern und seine Armee (wie Anm. 3), 300, Nr. 163.

13 Alto Brachner, Die Münchener Optik in der Geschichte. Entstehung, Unternehmungen, Sternwarten, Lokalitäten, Ausbreitung 1750–1984, München 1986, 113–118, 160–165. – Roth, Joseph von Fraunhofer (wie Anm. 9), 49–63. – Hans Jebsen-Marwedel, Joseph von Fraunhofer und die Glashütte in Benediktbeuern, München 1982, 11–26. – Ilse Mackenthun, Joseph v. Utzschneider. Sein Leben, sein Wirken, seine Zeit. Ein Beitrag zur bayerischen Wirtschaftsgeschichte [= Neue Schriften-reihe des Stadtarchivs München 11], München 1958, 125f. – Hans-Peter Sang,

20 Wie Anm. 10, 3. Konvolut; Gebäudebe-schreibung »G. Die Sommerabtei«, einge-legt im Produkt v. 6.II.1818; 1. Konvolut, Unternummer 5 ad 150. – KAM, A XIX, Bund 161. – Bayern und seine Armee (wie Anm. 3), 304. – Vgl. Leo Weber, Kloster Benediktbeuern (Großer Kunstführer 23), Regensburg 2003, 59–61. Die Salesianer Don Boscos sind seit 1930 im Kloster Benediktbeuern: Leo Weber (Hg.), Kloster Benediktbeuern. Gegenwart und Geschichte,Benediktbeuern 1981, 9–80.

21 Jebsen-Marwedel, Joseph von Fraunhofer (wie Anm. 13), 12. – Sang, Joseph von Fraunhofer (wie Anm. 13), 64.

22 Vgl. Fotos von P. Dr. Raymund Luschin SDB (Zimmergestaltung im Jahre 2002).

23 Carl Max von Bauernfeind, Gedächtnisrede auf Joseph von Fraunhofer zur Feier seines hundertsten Geburtstags, München 1887, 16. Vgl. Franz Past, Johann Georg von Soldner (1776–1833) und seine Zeit (Veröf-fentlichungen der Bayerischen Kommission für die internationale Erdmessung der Baye-rischen Akademie der Wissenschaften; Astronomisch-Geodätische Arbeiten, Heft Nr. 62), München 2005.

24 Wie Anm. 10, 1. Konvolut, Nr. 21.25 Textaufschrift auf der Spanschachtel mit

dem Wappen von Joseph von Fraunhofer: KLAB, Abtlg. »Weltliche Zeit«, Fraunhofer.

26 ADB 21, 480. – Roth, Joseph von Fraunhofer(wie Anm. 9), 90f. – KAM (wie Anm. 10), 3. Konvolut, Produkt v. 6.II.1818. – Vgl. Stahl (wie Anm. 13), 137, 151–153.

27 Wie Anm. 10, 1. Konvolut, Unternummer 7.

AbbreviationsADB: Allgemeine Deutsche BiographieBayHStAM: Bayerisches Hauptstaatsarchiv MünchenKAM: Kriegsarchiv MünchenKLAB: Klosterarchiv Benediktbeuern

Joseph von Fraunhofer. Forscher, Erfinder, Unternehmer, München 1987, 24f. – Wolfgang Stahl, Joseph von Utzschneider und seine Bedeutung für die deutsche optische Industrie, München 1929, bes. 116–171.

14 Wie Anm.10, 1. Konvolut, Unternummer 5 ad 172; Unternummer 25 (Rückseite).

15 Ebd., dazu a. a. O. 3. Konvolut: Gebäudebe-schreibung (»Abschrift«), eingelegt im Produkt v. 6.II.1818, fol. 2: – Dabei liegt ein Übersichtsplan von den Klostergebäuden aus dem Jahre 1818, Buchstabe o. (Die beiden großen Schmelzöfen in der »Glas-Ofen-Hütte« sind vermutlich in späterer Zeit erneuert worden). – Vgl. Carl R. Preyß, Joseph von Fraunhofer. Optiker – Erfinder – Pionier [= Stöppel-Kaleidoskop 203], Weil-heim 1989, 53.

16 Wie Anm. 10 – 1. Konvolut, Unternummer 16: »G. gemeine Glashütte u. Glas-Schleife-rey«. – NB: Es wird unterschiedlich »Glas-hütte« und »Glaßhütte« geschrieben. – 1. Konvolut, Unternummer 10 ad 98, 99. – Brachner, Die Münchener Optik (wie Anm. 13), 117f.

17 Wie Anm. 15 – Josef Kirmeier /Evamaria Brockhoff (Red.), Die historische Fraunhofer Glashütte in Benediktbeuern (Begleitheft zur Ausstellung »Glanz und Ende der alten Klöster. Säkularisation im bayerischen Oberland 1803«), München 1990, 18. Im September und Oktober 2005 wurden die Fundamente der »gemeinen Glashütte« bei Aushubar beiten für den Neubau der »Kath. Stiftungs fachhochschule für soziale Arbeit«freigelegt. Vgl. Stefan Biermeier M.A., SingulArch. Grabungen. Grabungsbericht, Benediktbeuern 2005, Westbau II.

18 Roth, Joseph von Fraunhofer (wie Anm. 9),49. – Sang (wie Anm. 13), 50 f., 56. – Jebsen-Marwedel, Joseph von Fraunhofer (wieAnm. 13), 25. – Brachner, Die MünchenerOptik (wie Anm. 13), 147–150. – Preyß, Joseph von Fraunhofer (wie Anm. 15), 51f.,62: »Fraunhofers neue Denkweise ... auf wissenschaftlicher Grundlage gab ein signifi-kantes Beispiel weit über die Optik hinaus«(S. 52). – Kirmeier /Brockhoff (wie Anm.17),8f., 14 (Wolfgang Jahn). – Stahl (wie Anm.13),138–144.

19 KAM, Remonte Inspektion und Depots.Bund 211, Unterbund Fraunhofer, Produkt4. – Roth, Joseph von Fraunhofer (wie Anm.9), 43–48. – Sang, Joseph von Fraunhofer(wie Anm.13), 39–41. – A. Seitz, JosefFraun hofer, in: Deutsche optische Wochen-Schrift 11 (1925) Nr. 41, S. 626. – Brachner,Die Münchener Optik (wie Anm. 13), 121.


Christoph Mewesgives an account of the restoration ofthe historic glassworks in Benedikt-beuern and explains the concept be-hind today’s, more extensive exhibition.

Conservation of the historic site

For many years, the Fraunhofer-Gesellschaft has taken a special interestin the glassworks founded by Josephvon Fraunhofer. Every effort has been made to conserve the authenticcharacter of this historic site as far aspossible, only making alterations wherenecessary to assure the structural integrity and safety of the building andimprove access.

The 175th anniversary of Fraunhofer’sbirth in 1962 provided the impetus to launch a new conservation programto restore the old building. One of the many people who lent their supportto this project was Hans Jebsen-Marwedel, who published a special anniversary paper on the life and worksof Joseph von Fraunhofer and the history of his workshop in Benedikt-beuern.

The exhibition:Glassworks and workshop

The historic glassworks under-neath the spires of Benedikt-beuern Abbey.

Exhibition


Architectural features of the glassworks

The original structure of the glassworksconsists of a barn-like timber-framedbuilding with wooden planking on the side elevations, resting on a single-story masonry wall, with visible tiebeams marking the interface betweenthe two elements of the construction.A number of small windows on therear elevation overlook the orchard be-longing to the Abbey. On the side facing the road, a more recently addeddouble doorway serves as the en-trance. It is the only opening in theotherwise windowless façade. In Fraunhofer’s day, there was a millstreamflowing parallel to the road. It led to a waterwheel connected to a shaftthat drove a stamping mill. The originalmain entrance was situated in thenorthwest wall of the building, and accessed via a bridge over the stream.It was in use until the 1980s, but hasnow been closed off.

The southwest gable end of the glass-works adjoins the former monasterywashhouse, which once also housedthe workshop that Fraunhofer used forgrinding lenses. The building’s unlinedsaddle roof is open to the rafters andrests on timber crossbeams that inplaces provide accessible attic space.Certain of the plain tiles that cover theroof have been replaced with authen -tic period tiles of the same design, torepair leaks. The load-bearing structurewas reinforced a few years ago by discretely adding metal tie beams wherenecessary. The floor inside the glass-works consists of unevenly laid brickwork and smooth slabs of naturalstone. The interior consists of a singlelarge room containing two impressivepot furnaces and the associated paddlemixers for the manufacture of glass.

The restoration project

In 1991, thanks to a joint initiative by the Haus der Bayerischen Geschichte(Centre of Bavarian History) and theFraunhofer-Gesellschaft, the historicglassworks was transformed into a modern scientific and historical mu-seum and study center.

The restoration work enabled items directly related to Fraunhofer’s work tobe exhibited in their authentic setting.One of the display cases containsFraunhofer’s personal beer mug along-side telescopes and a theodolite.

Glass screens set in a framework ofgalvanized steel protect the valuableexhibits without distracting attention.Explanative texts and images printedon the glass provide visitors with information and at the same time serveas a protective barrier, also coveringthe mouth of the glass furnaces. In ad-dition to the telescopes and a cast-metal bust of Joseph von Fraunhofer,many visitors are fascinated by an experimental setup donated by theFraunhofer Institute for Laser Tech -nology ILT in Aachen. The hands-ondisplay permits visitors to visualize the transmission and diffraction of light through lenses, and appreciatethe quality of the antireflective lensescreated by Fraunhofer.

The workbenches in Fraunhofer’sworkshop used to grind and polish lenses.


The extension of the museum:Fraunhofer’s workshop

In 2006, Carl R. Preyß, a foundingmember of the Fraunhofer-Gesell schaft,Pater Leo Weber, Salesian pastor inBenediktbeuern Abbey, a group of Fraunhofer experts, and ChristophMewes from the Fraunhofer-Gesell -schaft’s department for constructionproj ects and property, drew up plans for an exhibition in Benedikt-beuern featuring the tools and optical in struments with which Josephvon Fraunhofer had worked 200 years ago. Until then, these items hadbeen stored in the vaults of theDeutsches Museum and the MunichStadtmuseum, owing to the fact that the historic glassworks was unableto provide appropriate display facilitiesconforming to modern-day museumstandards. Faced with this dilemma,the initiators of the project consultedarchitect Knut Prill (Baldauf·Prill Architekten, Schongau) with the aim of reopening the passage between the glassworks and the former Abbeywashhouse, which had been closedoff. This space, which once housedJoseph von Fraunhofer’s lens-grindingworkshop, nowadays serves as theguest wing for visitors to the monastery.Two of the rooms have now been converted into an additional exhibitionroom for the mu seum, thanks to thegenerosity of the monks who agreed to donate part of their guestfacilities for this purpose.

Taking extreme care to preserve the ex-isting vaulting, the partition walls wereremoved, the existing hallway wasclosed off with a steel door to meetfire safety requirements and concealedbehind a jib door, and two windowswere inserted in a style that harmo-nizes with the building’s outward ap-pearance while at the same timeproviding the necessary security for exhibition rooms.

Visitors can now step out of the glass-works building onto a viewing plat-form with glass screens on three sidesthat gives a clear all-round view of the current exhibition.

The restored glassworks with themelting furnaces. The round tub in the foreground is a paddlemixer in which the molten glasscould be immersed and cooled.


Whereas the exhibits in the glassworksbuilding focus on the manufacture of glass from silica sand (1Glass manu-facturing), the new exhibition spacecontains a series of displays devoted tothe following topics:

2 Glass forming3 Optical components4 Metalworking5 Mechanical components6 Optical instruments7 Samples of unprocessed glass

The largest items on display, such as a gear-milling machine and a glass grinding machine, which weigh closeto 500 kilograms apiece, are so bulkythat they had to be brought into the exhibition room before the carpen-ter had completely assembled theframe and glass screen of the viewingplatform.

The number of objects on display mayseem huge compared to what washere before, but there is still a consid-erable collection of Fraunhofer materialin the two donor museums, waiting tofind a new home in the historic glass-works in Benediktbeuern.

Structurally, it would be relatively easyto add further space to the new smallmuseum.

5 Mechanical components

Fraunhofer‘s historic workshop in Benediktbeuern

6 Optical instruments

3 Optical components

4 Metalworking

7 Samples of unprocessed glass

1 Glass manufacturing

2 Glass forming


CarI R. Preyßdescribes Joseph von Fraunhofer’shuge influence on the course of scientific, technological and industrialprogress.

Fraunhofer’s ingenious approach to optical research

Joseph von Fraunhofer was born in1787 in Straubing, south Germany. Towards the end of his all-too-brief life,he made a discovery that would oneday lead to the emergence and re-markable rise of a whole new branchof industry: the physical relationshipbetween the resolution of a microscopeand the wavelength of light.

Fifty years later, Ernst Abbe in Jena re-discovered this same relationship,which was to form the basis for theoutstanding success of a companynamed Zeiss. Speaking at a meeting inJena to celebrate the centenary of Fraunhofer’s birth in 1887, he said:“Fraunhofer’s early demise was an irretrievable loss for both practical andexperimental optics. The revolutionaryideas on which he was working duringthe latter years of his life would haveadvanced the field of optics by severaldecades if they had been implementedat the time. Instead, they were interredwith him in his grave and, as historyconfirms, it took the work of anothertwo generations of scientists to retreadthe same path, following in his foot-steps …”

Fraunhofer’s significance

Fraunhofer’s

Joseph von Fraunhofer.


This is not the only reason why Fraunhofer is considered as a geniusahead of his time; other remarkablefacts include:

– Fraunhofer amassed his consider-able knowledge on his own, as a simple apprentice without any academic training.

– Besides being a scientist, he was also a gifted entrepreneur.

– The optical systems he created wereof a far superior quality, enabling him to build the most highly efficientastronomical telescopes of his day.

– He was one of the first to under-stand and exploit the wave principlesof light.

– His approach to the development and manufacture of technical systems was entirely without prece-dent, and formed the basis for modern industrial working practice.

Support for an ambitious young man

There have been many accounts ofFraunhofer’s youth, often verging onthe melodramatic. There is no doubtthat he suffered hardship, but that wasalmost normal in those days. Helearned a respectable trade, supportedby one of his sisters after his parentsdied, being her only brother. The familyowned a fine house in Straubing andthe rights to work as a glassmaker. The thing that really oppressed him wasthe narrow-mindedness of his master,who saw no necessity for theoreticaltraining and discouraged all forms ofbook learning.

The young Fraunhofer’s fortunes wereturned around by an unexpected accident, when his master’s house inThiereckgäßl in Munich collapsed in1801, an event from which the youngman barely escaped with his life. Thehomeless youngster with an insatiablethirst for knowledge was taken underthe wing of Joseph von Utzschneider, a progressive entrepreneur and politicaleconomist, and the Bavarian prince-elector Maximilian IVJoseph grantedhimgenerous financial support. Anotherof his sponsors was the highly educatedBenedictine pastor Ulrich Schiegg, who was a renowned authority in mat-ters of science and engineering. With their support, Fraunhofer was able to continue his self-education and de-velop his ideas.

Fraunhofer’s extraordinary talent finallycame to the fore in 1806, whenUtzschneider recruited the 19-year-oldto work in his factory for optical instru-ments because he was in urgent need of someone capable of manufac-turing the high-quality lenses to gowith the finished, but still “blind” in-struments. Fraunhofer broke with conventions to develop his own meth-ods, and before long he was producinglenses that exceeded all expected requirements in terms of quality, quan-tity and costs.

The company had been originallyfounded by the noted engineer and in-ventor Georg von Reichenbach, to-gether with Utzschneider. In 1807, thefactory was relocated from Munich tothe abbey buildings in Benediktbeuernthat Utzschneider had recently pur-chased. Fraunhofer, who was only 21at the time, drew up a new “businessplan” and requested that he should be taken on as a partner. This was thestart of his career as an entrepreneur,and in 1814 he became sole manager.

Blazing new trails for science andindustry

It was at this point that Fraunhoferonce again demonstrated his talent fororiginality. After having revolutionizedmanufacturing processes, he now wenton to develop new instruments of un-precedented quality and, furthermore,turned his attention to theoretical science and started to investigate thewave structure of light.

This boosted his success as a manufac-turer. His telescopes were delivered tocustomers all over the world andhelped to advance astronomical sci-ence. His large telescopes and heliome-ters were installed in all the majorobservatories, including those of Mu-nich, Moscow, Cincinnati, Christiania,Greenwich, Mexico and Sydney. The Dorpat refractor, which was exhib-ited in public before being shipped to the observatory in Russia, representedthe epitome of precision mechanicsand optical engineering, and becamesynonymous with technologicalprogress.

Significance


Fraunhofer was no less successful as atheoretical scientist. He systematicallystudied and measured the absorptionlines of the solar spectrum, initially as ameans of establishing objective stan-dards for the development and testingof optical glass. Now known as“Fraunhofer lines”, they have since become part of the standard terminol-ogy in the world of physics and havemade a significant contribution toprogress in spectral analysis and astro-physics.

For Fraunhofer, this was just the begin-ning of a long quest to elucidate the nature of light. He subsequentlyprovided unequivocal proof of Young’swave theory, and was the first to produce absolute wavelength measure-ments using the optical diffraction filters that he had invented himself. Hisresults deviate only by parts per thou-sand from those measured using mod-ern instruments

Outstanding achievements crowned by early recognition

As a result of this work, Fraunhofergained the recognition of the interna-tional scientific community and was accepted as a member of the RoyalBavarian Academy of Sciences andother scientific bodies, as well as re-ceiving an honorary doctorate from theUniversity of Erlangen, where he gavelectures on optics in his capacity asprofessor. In 1824, King Max I Joseph

of Bavaria, who had faithfully followedhis fortune since the time when theyoung apprentice glazier had escapedthe destruction of his master’s house,awarded him the title of Knight of theOrder of Civil Service of the BavarianCrown, enabling him to join the ranksof the nobility.

However, these honors do not reflectwhat was possibly Fraunhofer’s mostenduring achievement, which was theintroduction of entirely new methodsof developing and manufacturing industrial products. He was one of thefirst to recognize the limits of existingmethods, preferring to explore all manner of possible alternatives in termsof materials, processes and productssystematically and without preconceivedideas, and developed new materials,manufacturing machines and test meth -ods. This approach ruled out sources of human error and inaccuracy, andgave the manufacturer complete controlover quality, yield, time and costs. Itwas an entirely new way of thinking.

Ernst Abbe, too, was aware of this factwhen he wrote that the thought of allowing the forming hand merely to serve the embodiment of a perfectedidea represented an absolutely novelapproach at the time. He went on to say that, “All true progress – evenwhere it did not derive directly fromFraunhofer’s groundbreaking work –came into being this way.”

A revolutionary thinker for futuregenerations

Fraunhofer’s ideas were thus thesource of modern industrial methodsused to develop new materials, com-ponents, machines and instrumentsand to devise apparatus, working tech-niques and test equipment.

It was therefore highly appropriate that,in 1949, an institution devoted to applied research should choose to baseitself on Fraunhofer’s name and principles: the Fraunhofer-Gesellschaft.

The legacy of Fraunhofer’s work hasbeen highly influential, and is still alivetoday. A fortunate combination of circumstances has ensured that a greatdeal of the material evidence of hiswork has been preserved intact, andmost particularly his glassworks atBenediktbeuern Abbey. Moreover, manyimportant items from his workshophave been saved, especially throughthe foresightedness of Dr. Loher, whoseinitiative led to the creation of the Fotomuseum (museum of photography)in Munich. A part of this collection is now open to the public and, what’smore, in a room that Fraunhofer himself used for manufacturing preci-sion optics.

Many more items are being kept instorage, waiting for the day when theycan be displayed to the public. Fraunhofer’s immense significance tothe history of physical optics, astronomy,and industrial manufacturing methodsmerits a small museum devoted to production engineering, which providesa suitable complement to the valuablecollection of instruments on display inthe Deutsches Museum.


References

Bayern und seine Armee. Eine Ausstel-lung des Bayerischen Hauptstaats-archivs aus den Beständen des Kriegs-archivs, Rainer Braun u.a. München1987 (Ausstellungskataloge der Staatlichen Archive Bayerns Nr. 21).

Brachner, Alto: Die Münchener Optik in der Geschichte. Entstehung, Unternehmungen, Sternwarten, Lokali-täten, Ausbreitung 1750–1984, Diss.München 1986.

Brachner, Alto/Seeberger, Max (Hg.): Joseph von Fraunhofer 1787–1826.Ausstellung zum 150. Todestag, Deutsches Museum, München 1976.

Jebsen-Marwedel, Hans: Joseph von Fraunhofer und die Glashütte in Benediktbeuern, München 1982.

Joseph von Fraunhofer 1787–1826,Ausstellung zum 200. Geburtstag, Konzeption: Johannes Prammer, Straubing 1987 (Katalog des Gäubo-denmuseums Straubing Bd. 10).

Junkelmann, Markus: Joseph vonFraunhofer – Pionier der modernenForschung, in: Unternehmer – Arbeit-nehmer. Lebensbilder aus der Frühzeitder Industrialisierung in Bayern, hg. v. Rainer A. Müller, München 1985,S. 76–80 (Veröffentlichungen zur Bayerischen Geschichte und Kultur Bd. 7/85).

Kohler, Ernst: Georg von Reichenbach,Das Leben eines deutschen Erfinders,München 1933.

Kratz, Otto Paul /Renatus, Elisabeth:Zur Geschichte der Glashütten in Benediktbeuern, in: Kultur und Technik7 (1983), S. 249 –256.

Mackenthun, Ilse: Joseph v. Utzschnei-der, sein Leben, sein Wirken, sei ne Zeit. Ein Beitrag zur bayerischen Wirt-schaftsgeschichte, München 1958.

Preyß, Carl R.: Joseph von Fraunhofer.Optiker – Erfinder – Pionier, Weilheim1989.

Preyß, Carl R.: Joseph von Fraunhofer.Physiker – Industriepionier, (o.O.) 2007. Veränderter Nachdruck des Buchs »Joseph von Fraunhofer. Optiker – Erfinder – Pionier«.

Rollwagen, Walter: Joseph von Fraunhofer, München 1977.

Sang, Hans-Peter: Joseph von Utz-schneider (1763–1801). Sein Leben,sein Wirken, Diss. München 1985.

Sang, Hans-Peter: Joseph von Fraun-hofer. Forscher, Erfinder, Unternehmer,München 1987.

Schneider, Anton: Der Gewinn desbayerischen Staates von säkularisiertenlandständischen Klöstern in Altbayern,München 1970 (Miscellanea Bavarica Monacensia 23).

Seitz, Adolf: Joseph Fraunhofer undsein optisches Institut, Berlin 1926.

Utzschneider, Joseph von: KurzerUmriß der Lebens-Geschichte desHerrn Dr. Joseph von Fraunhofer, in:Kunst- und Gewerbeblatt des polytechnischen Vereins für das König-reich Bayern 12 (1826), S. 411– 424.

Editorial notes

Editorial teamDr. Martin ThumChrista Schraivogel (picture editor)

AuthorsDr. Wolfgang Jahn, Haus der Bayerischen Geschichte(Centre of Bavarian History)Dr. Josef Kirmeier, Haus der Bayerischen Geschichte(Centre of Bavarian History)Christoph Mewes, Fraunhofer-Gesellschaft Carl R. Preyß, Founding member of the Fraunhofer-GesellschaftPater Prof. Dr. Dr. Leo Weber, Benediktbeuern Abbey

The contributions by Dr. WolfgangJahn and Dr. Josef Kirmeier, and the photos on pages 5 –13, 15 and 22, are taken from “Die historischeFraunhofer-Glashütte in Benedikt-beuern”, published jointly by Fraunhofer-Gesellschaft and Hausder Bayerischen Geschichte (Centreof Bavarian History), München1990.

LayoutGestaltungsbüro Hersberger SGD,Munich

ProductionMarie-Luise Keller-Winterstein

English editionBurton, Van Iersel & Whitney GmbH,Munich

Photo acknowledgmentsAlexander Heck: 5 – 8,11,13 –15, 21Deutsches Museum: 17Bernd Müller: 14, 23 – 29, 34 – 35,Hans Wiedemann: 7 right, 9, 22

Reproduction of any material is subject to editorial authorization.

www.fraunhofer.de

© Fraunhofer-Gesellschaft, München 2008

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