astrolabe. - breker

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1 Astrolabe. Expert report by S. Maslikov, Cand.Sc. Physics and Mathematics. Private collection, Moscow. Provenance: purchased at an Austrian art auction house about 20 years ago. An astrolabe consists of a mater, spider, 4 plates, alidade, axle, pin in a form of a curved dagger, suspension with a ring and a cord. Total weight: 342 gr. A brazen body is 92 mm in diameter and 7 mm thick. The throne on the front side is decorated with a flower with 9 large petals resembling a sunflower; below there are two more flowers with stems and leaves. The background is treated with a square- headed punch. The back side of the throne is decorated with interweaving floral design stems and leaves, with rounded grain-shaped punch marks on the background. Front and back side of the throne. The limb on the FRONT is divided into 360 degree divisions. Every five degrees are grouped and signed by the Abjad system, i.e. the numbers are in Arabic letters. The counting starts from the horizontal diameter on the right and left and goes up and down to the vertical diameter. That means that all four quadrants are signed with numbers from 5 to 90 degrees. This method of marking refers to the end of the 18th - early 19th centuries. This scale was used in conjunction with the spider pointer (a dash at the top of the spider) to measure the position of the vernal equinox relative to the zenith. It is quite rare. Thus, in the vast collection of the National Museum of American History (Washington), there are only four such instruments - №№ 58, 61, 62, 66 (Gibbs, Saliba, p. 25) of 48 astrolabes available. GAZETTEER. On the bottom of the mater in two circles, there is a table of coordinates of 38 geographical points (23 in the outer circle and 15 in the inner circle). The header column (the first column to the left of the vertical diameter) contains the name of [city] دالبلا- bilad, longitude لوط- aṭwāl, latitude ضرع- curūḍ, and qibla فارحنا- inḥirāf.

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Page 1: Astrolabe. - Breker

1

Astrolabe.

Expert report by S. Maslikov, Cand.Sc. Physics and Mathematics.

Private collection, Moscow.

Provenance: purchased at an Austrian art auction house about 20 years ago.

An astrolabe consists of a mater, spider, 4 plates, alidade, axle, pin in a form of a curved dagger,

suspension with a ring and a cord. Total weight: 342 gr.

A brazen body is 92 mm in diameter and 7 mm thick.

The throne on the front side is decorated with a flower with 9 large petals resembling a sunflower;

below there are two more flowers with stems and leaves. The background is treated with a square-

headed punch. The back side of the throne is decorated with interweaving floral design – stems

and leaves, with rounded grain-shaped punch marks on the background.

Front and back side of the throne.

The limb on the FRONT is divided into 360 degree divisions. Every five degrees are grouped and

signed by the Abjad system, i.e. the numbers are in Arabic letters. The counting starts from the

horizontal diameter on the right and left and goes up and down to the vertical diameter. That

means that all four quadrants are signed with numbers from 5 to 90 degrees. This method of

marking refers to the end of the 18th - early 19th centuries. This scale was used in conjunction

with the spider pointer (a dash at the top of the spider) to measure the position of the vernal

equinox relative to the zenith. It is quite rare. Thus, in the vast collection of the National Museum

of American History (Washington), there are only four such instruments - №№ 58, 61, 62, 66

(Gibbs, Saliba, p. 25) of 48 astrolabes available.

GAZETTEER. On the bottom of the mater in two circles, there is a table of coordinates of 38

geographical points (23 in the outer circle and 15 in the inner circle). The header column (the first

column to the left of the vertical diameter) contains the name of [city] دالبلا - bilad, longitude لوط

- aṭwāl, latitude ضرع - curūḍ, and qibla فارحنا - inḥirāf.

Page 2: Astrolabe. - Breker

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Numerical values are given by the Abjad system in degrees and minutes of arc. Zero is indicated

by a small circle.1 City names follow counterclockwise (see Table 1). In the center of the gazetteer

in four quadrants the four intercardinal directions are engraved (starting from the upper left

quadrant counterclockwise). They have a purely decorative function:

Southeast sarqi ganubi شرق جنوب,

Northeast sarqi samali شرق شمال,

Northwest gharbi ganubi غرب جنوب,

Southwest gharbi samali غرب شمال.

Table 1 – Gazetteer.

№ Name (city) Arabic script Longitude Latitude Qibla Notes

Outer circle

1 Baghdad 33 80 بغداد ? ?

2 Tabriz تبريز

82 38 15 30 The same as Qibla №15

(Gibbs)

3 Marāgheh 30 15 20 37 82 مراغه Qibla is incorrect

4 Ardabil 15 38 20 82 اردبيل ? Qibla is incorrect

5 Shahrazur 35 35 35 35 20 82 شهرزور

6 Abadan بادان Rarely found 30 25 20 30 84 ع

7 Qazwīn ‎‎قزوين

85 36 27 30 The same as Qibla №15

(Gibbs)

8 Qum ‎‎ قم ‎ 85 30 35 40 32 ?

9 Sāwa (Saveh) 14 29 35 85 ساوه

10 Kāshān قاشان

86 34 45 36 8 The same as Qibla №15

(Gibbs)

11 Iṣfahān 40 40 25 32 40 86 اصفهان

12 Yazd يزد

89 30 ? 47 17 The same as Qibla №15

(Gibbs)

13 Shīraz زسيرا ‎‎ 88 29 ? 31 ?

هاركشبا ? 14 89 33 33 ? 33

15 Kirman 63 40 30 30 92 كرمان

16 Neyšâbur نيشابور‎ 92 30 36 27 46

17 Tus سطو 92 30 37 45 35

18 Herāt 30 34 20 94 هرات ?

19 Marw 40 37 ? 97 مرو ?

20 Bukhara 47 ? 39 30 97 بخارا?

21 Samarqand

سمرقند

98 40 49 All three coordinates are

the same as on №15

(Gibbs). Typical values are

99, 39, and 14.

22 Balkh 30 35 41 37 101 بلح

23 Khujand حجند

100 25 41 56 ? Longitude 100 has №86

(Gibbs)

Inner circle

24 Dimashq 30 33 40 70 دمشق ?

25 Bayt al-maqdis المقادس بيت 60 ? 30 20 20 Qibla is incorrect

26 Miṣr 30 67 20 30 63 مصر Qibla is incorrect

1 Such a designation of zero is not generally accepted and may provide additional information.

Page 3: Astrolabe. - Breker

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27 Rahbeh ? 6 ?46 ? 34 ? 74 يهند? Qibla is incorrect

?48 30 34 33 هدنه ? 28

29 Jiddah ? 31 76 ودن ?

30 Habash ? 40 44 ? ? حبشه Qibla is incorrect

31 ? 84? 10 44 44

32 ? 86 37? 69 30

33 Hurmūz

(Ormuz) هرموز

92 30 ? 45

34 Thanah 69 20 29 102 تانه

35 Sistan ثانسس 97 32 30 36 4

36 Kashmir شمرك 105 35 40 60 7

37 Multan 4 71 40 29 35 107 ملتن

هكدبم ? 38 86 30 29 37? 77 13?

An analysis of the table revealed some interesting features: several azimuths of qibla accurately

repeat the astrolabe №15 from the Washington catalogue [Gibbs, Saliba, pp. 64-65]. This indicates

the possible roots of this astrolabe, as well as the astrolabes from the Museum of the East

(Moscow) - the Persian city of Kerman. More specifically, this fact is a clear indication of the

traditions of the masters of the city of Kerman.

Most of the cities are identified; their coordinates correspond to generally accepted values in the

past. This clearly indicates the authenticity of the instrument. The estimated time of creation of the

gazetteer is the end of the 18th - beginning of the 19th century.

SPIDER: diameter is 75 mm. It contains pointers of 26 stars (see Table 2). Symmetrically located

pointers of stars №23 (Alpha Cygni) and №17 (alpha of the Northern Crown) are made in the

form of bird heads. Vega is usually depicted this way (Alpha Lyra, №20). There is a handle for

rotating the spider, located to the right in the area of the Spica star (№ 15). Some inscriptions are

difficult to read as if they were made by another hand.

Table 2 – Astrolabe Stars.

№ Name in

Arabic script Transliteration English translation

Identifi-

cation

الحوت بطن 1 baṭn al-ḥūt the belly of the fish β And*

fam al-qayṭus the mouth of Cetus γ Cet فم القيطس 2

ghūl [the head of] the Demon β Per غول 3

عيوق 4cayyūq (?) α Aur

α Tau ? درر 5

rijl the left foot β Ori رجل 6

? ? رني 7

مانيي 8 yamānῑyyah the southern Sirius α CMa

α UMa ? لا 9

sha’āmῑ[yyah] the northern Sirius α CMi شامي 10

fard the solitary one of the water snake α Hya فرد 11

qalb al-asad the lion’s heart α Leo قلب الأسد 12

13 ? γ Crv

al-canāq the badger (a desert animal) ζ UMa العناق 14

عزللاا 15 al-aczal the unarmed simāk α Vir

16 ? α Boo

ةالفك 17 al-fakka the bright one of the broken vessel α CrB

Page 4: Astrolabe. - Breker

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al-ḥawwā’ head of the snake-charmer α Oph الحوا 18

-qalb al قلب العقرب 19caqrab the scorpion’s heart α Sco

20 ? α Lyr

ṭā’ir the flying eagle α Aql ا‎‎طائر 21

dhanab al-jadī the tail of the goat δ Cap ذنب الجدي 22

al-dajāja the bird’s head α Cyg ? الدجاجة 23

24 ? β Peg

al-khāḍῑb the stained hand β Cas الخضيب 25

26 ذنب قيطس

dhanab qayṭus

[janūbῑ]

the southern tail of Cetus β Cet

* β And - the only one star that is out of place. It must be inside the circle of the ecliptic.

The inscriptions marked with a question mark are illegible, although it is clear what the stars

should be there.

One star is incomprehensible - №7 - between the beta of Orion and Sirius.

Most of the stars are identified, placed and signed correctly. The spider made by the hand of an

experienced master and, most likely, can be dated, like other elements, back to the end of the 18th

- the beginning of the 19th century.

PLATES: 4 pcs. The fixation slot locates underneath. Just below the middle line of the plate, there

are two ornately shaped cartouches with inscriptions: on the right- the latitude (curūḍ - htiw (عرض

Page 5: Astrolabe. - Breker

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a corresponding value, on the left - the duration of the longest day (sācātuhu - ehT .(ه ساعات

daytime length is indicated under the cartouche in hours and minutes.

Fragment of the plate 2b with inscriptions.

Plate parameters:

1a - 32º (14 h. 07 min.);

1b - 34º (14 h. 18 min.);

2a - 34º (14 h. 18 min.) – similar to side 1b;

2b - 36º (14 h. 30 min.) - next to the digit 14, digit 13 was, possibly, mistakenly inscribed, the

digit 30 is rotated at the right angle (see fig.);

3a - 38º (14 h. 40 min.);

3b - 40º (14 h. 52 min.);

4a - 22º (13 h. 21 min.) - for the latitude of Mecca (21º40 ');

4b - horizon lines for all latitudes, grouped in four sectors.

The degrees of latitudes on the plate correctly correspond to the maximum daylight length.

On each plate, there are all principle circles: the tropics of Cancer and Capricorn, the equator,

as well as the vertical diameter (meridian), and the horizontal diameter (straight horizon).

Circles of equal heights (Almucantarats) drawn in increments of 6º. The circles from 6 to 90 are

signed in the Abjad system. The inscriptions are duplicated by Indo-Arabic numerals

١٢٣٤٥٦٧٨٩, which is typical of astrolabes from Lahore. Equal azimuth lines are drawn and

signed below the horizon in increments of 10º. The numbering goes from east and west points

to the central meridian. The exception is the prime vertical, i.e. azimuth 0º, which is drawn

above the horizon. Hours are indicated by dotted lines and signed in the Abjad system. The

sides of the horizon are signed - east (Al-Mashriq قرشملا) on the left and west (Al-Maghrib

.thgir eht no (غرب م ال

Plate1a. 32 degrees latitude. The intersection points of the principle line shown in white circles - a characteristic

sign of the high quality of the plate manufacturing. The accuracy on other plates is slightly worse.

Page 6: Astrolabe. - Breker

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The horizon plate also contains lines for polar latitudes - 66º30 ', 78º, 84º. The astrolabe from the

Museum of the East in Moscow has the same lines (with more complete information) [Maslikov,

Sarma, 2016].

The high precision of plate manufacturing is especially well seen at the intersection points of four

principle lines, one of which is a straight line - the straight horizon, and three radial arcs - the

inclined horizon, the prime vertical and the equator (in the figure, these two intersection points are

indicated by white circles). This proofs that the master performed his work with skill. However,

this is indicated by other elements as well, for example, the correct position of circles of equal

height.

BACK. The limb is divided into degree divisions; every 5th degree is signed. The counting goes

from the horizontal diameter up and down, in the same way as on the Front of the astrolabe. The

design of the scales is also identical.

In the upper left quadrant - the scale of the sines. In fact, there are two scales; the smaller one is

embedded in the larger one. The outer scale has the horizontal lines drawn per 5 degrees; they are

concentrated in the upper part. The inner scale has radial lines and concentric arcs. Both those and

others are indented in increments of 5 units, the arcs are signed from the center to the outer edge:

5, 10, 15 ... 60. The purpose of this scale is to solve the equations of the form sin A = sin B / sin C

[Morrison, p. 130]. The scale of the sines is made with low accuracy and less neat, which is in

discord with other elements of the astrolabe as if the master entrusted its manufacture to his

inexperienced apprentice.

In the upper right quadrant half of the shadow square is placed, inside of which is a table of

triplicities. Triplicities or trigons are the astrological breakdowns of the Zodiac signs according to

the elements (fire, earth, air, water). Each Zodiac sign is ruled by a planet, one by day, and the

other by night. For example, the sign of Aries is ruled by the Sun during the day and by Jupiter at

night. In the table, in order to keep it short, planets are indicated by one letter (see table), and the

signs of the Zodiac are indicated by numbers: Aries - 0, Taurus - 1, Gemini - 2, Cancer - 3, Leo -

4, Virgo - 5, Libra - 6, Scorpio - 7, Sagittarius - 8, Capricorn - 9, Aquarius - 10, Pisces - 11.

Table 3 – Planets, their Arabic names, and short (single letter) designation.

Sun al-shams س الشمس Jupiter al-mushtari ے المشتري Saturn zuhal ل زحل Venus zuhara الزهرة

ه

Moon al-qamar ر القمر Mars al-mirrik خ المريخ Mercury al-utarid ک عطارد

Table 4 – Triplicities.

Cancer Scorpio Pisces Venus Mars Moon Mars Venus Moon

Gemini Libra Aquarius Saturn Mercury Jupiter Mercury Saturn Jupiter

Taurus Virgo Capricorn Venus Moon Mars Moon Venus Mars

Aries Leo Sagittarius Sun Jupiter Saturn Jupiter Sun Saturn

Triplicities Daytime ruler Nighttime ruler

Page 7: Astrolabe. - Breker

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In the lower half of the disc a series of semi-circular scales are placed. Scales are not signed. Their

value will be given below. For convenience, we number them from I to VIII as shown in the

figure.

VIII – Mansions of the Moon

VII – Borders of Decans (10, 20, 30)

VI – Decan rulers

V – Term rulers

IV – Zodiac constellations

III – Length of Terms

II – Cotangent scale

I – Degree scale

Scales on the lower half of the back

The cotangent scales, which are located after the degree scale, made it possible to take the values

of these functions directly when measuring heights. To the left of the vertical line, there is a

duodenary scale, where the values of the cotangents are expressed in "fingers", i.e. 1/12, 2/12,

3/12, etc. On the right are the values in the "feet", i.e. 1/7, 2/7, 3/7, etc. For example, ctg 60 º =

0.577 (in the customary decimal system) = 7/12 (in the duodecimal system) / = 4/7 (in the

septenary system). So, for an angle of 60 degrees on the left scale, the alidade will indicate the

value 7, and on the right scale for the same angle, we will find the value 4, as it should be.

Therefore, it can be argued that these scales are made by an experienced master with skill, which

also indicates the authenticity of production.

The names of these two scales are written near the center. Calligraphic inscriptions are placed in

ornately shaped cartouches, decorated with flowers and additional lines. These inscriptions are

turned so that they are read from the center. Right one (in the picture) - fingers (ẓill-i aṣābic), left

one - feet (ẓill-i aqdām).

The Zodiac scale (scale IV) contains the names of 12 Zodiacal constellations, which begin on the

left side and go counterclockwise.

Table 5 – The Zodiacal constellation names.

Aries Taurus Gemini Cancer Leo Virgo

Page 8: Astrolabe. - Breker

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حمل ثور ل جوزاء ل سرطان ال سد ال عذراء الأ ال

hamal saur jauza saratan asad sunbula

Libra Scorpio Sagittarius Capricorn Aquarius Pisces

يزان م قرب ال ع قوس ال جدي ال و ال دل حوت ال الmizan akrab kaus jadi dalv hut

The TERMS (scales III and V) show the division of each degree of the Zodiac into five unequal

parts. Each term is ruled by a planet, the name of the planet on the scale is indicated by the last

letter of its Arabic name (as indicated in the table below). The method of division that we find

here is very ancient; it goes back to Ptolemy Tetrabiblos. And Ptolemy himself called this method

Egyptian, originating from the ancient Egyptian astrologers Nechepsos and Petrosiris (151 BC).

Such tables are to be found on many astrolabes from Lahore, including astrolabes from the

Museum of the East (Moscow). At the same time, our astrolabe is made with pinpoint accuracy

with no errors in the values of the length of terms (scale III). This accuracy proofs this astrolabe to

be the original and genuine instrument.

Table 6 – Term scales.

Zodiac

constellation

Ruling

planet

(scale V)

Length of

term

(scale III)

Aries

Jupiter 7

Venus 6

Mercury 8

Mars 5

Saturn 5

Taurus

Moon 8

Mercury 6

Jupiter 8

Saturn 5

Mars 3

Gemini

Mercury 7

Jupiter 6

Venus 5

Mars 7

Saturn 6

Cancer

Mars 7

Venus 5

Mercury 6

Jupiter 7

Saturn 5

Leo

Jupiter 6

Venus 5

Saturn 7

Mercury 6

Mars 6

Virgo

Mercury 7

Venus 10

Jupiter 4

Mars 7

Saturn 2

Zodiac

constellation

Ruling

planet

(scale V)

Length of

term

(scale III)

Libra

Saturn 6

Mercury 8

Jupiter 7

Venus 7

Mars 2

Scorpio

Mars 7

Venus 4

Mercury 8

Jupiter 5

Saturn 6

Sagittarius

Jupiter 12

Venus 5

Mercury 4

Saturn 5

Mars 4

Capricorn

Mercury 7

Jupiter 7

Venus 8

Saturn 4

Mars 4

Aquarius

Mercury 7

Venus 6

Jupiter 7

Mars 5

Saturn 5

Pisces

Venus 12

Jupiter 4

Mercury 3

Mars 9

Saturn 2

Page 9: Astrolabe. - Breker

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Decans divide each of the Zodiac constellation term into three equal parts of 10 degrees. Decans

are also of ancient origin. The scale VI shows the name of the ruling planet for each decan. Here is

the full Arabic name of the planet: mirrīkh (Mars), shams (Sun), mushtarī (Jupiter), zuhra

(Venus), cauṭārad (Mercury), zuḥal (Saturn), and qamar (Moon). The scale VII with auxiliary

numbers 10, 20, 30 facilitates orientation on the scale.

Table 7 – Decans (scales VI, VII).

Zodiac

constellation

Decans

10 20 30

Aries Mars Sun Jupiter

Taurus Venus Mercury Saturn

Gemini Mercury Venus Saturn

Cancer Moon Mars Jupiter

Leo Sun Jupiter Mars

Virgin Mercury Saturn Venus

Libra Venus Saturn Mercury

Scorpio Mars Jupiter Moon

Sagittarius Jupiter Mars Sun

Capricorn Saturn Venus Mercury

Aquarius Saturn Mercury Sun

Pisces Mercury Mars Saturn

Scale VIII - Mansions of the Moon (Arabic manāzil) - the division of the Zodiac into sections that

the Moon passes in one day. Since the Moon moves completely around the celestial sphere once in

about 27.3 days (sidereal period), as observed from the Earth, the number of lunar mansions was

assumed to be either 27 or later - 28. In our case, there are 28 mansions, so in one Zodiac

constellation there are 2 1/3 mansions of about 13° 50'. Each mansion comes under a specific

group of stars. List of mansions [Ackermann, p. 76–79]:

Table 8 – Mansions of the Moon (scale VIII).

1 sharaṭān

2 buṭayn

3 thurayyā

4 dabarān

5 haq’a

6 han’a

7 dhirā’

8 nathra

9 ṭarf

10 jabha

11 al-zubra / al-kharātān

12 ṣarfa

13 ‘awwa’

14 simāk al-a’zal

15 ghafr

16 zubanā

17 iklil

18 qalb

19 shawla

20 al-na’ā’im’

21 balda

22 dhābiḥ

23 bula’

24 su’ūd

25 akhbiya

26 muqaddam

27 al-mu’akhkhar

28 baṭn al-hūt / al-risha’

Page 10: Astrolabe. - Breker

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The names of the mansions are very neatly written.

ALIDADE has no scales - this confirms the late manufacturing of the tool. The target axis is offset

relative to the axis of rotation. There are two holes in the sighting device - large and small. The pin

has the rare form of a curved dagger or saber and not the traditional execution in the form of a

horse's head. Late astrolabe pins of the 18th century, stored in Greenwich, have a similar shape

[Charette, p. 267, 273].

Conclusion.

Unfortunately, the astrolabe has no direct indication of the year of its production and the name of

the master. This can be judged only by indirect data, such as scales design, a set of cities in the

gazetteer, a selection of stars on the spider, the composition of astrological information on the

back of the instrument, the design of the alidade and pin.

A number of factors (degree scale and pin shape, lack of scales on alidade) suggest the late

production of this tool - the end of the 18th - the beginning of the 19th century. However, the sets

of cities in the gazetteer and stars on the spider are made according to the rules of the craft of

much earlier instruments, dating back to the school of craftsmen from the city of Kerman of the

14th-15th centuries. The traditions of this school in the 16th-17th centuries were preserved in

Gilan, a city in the north of Persia and in Lahore, in India. It was here that the astrolabes were

made, having many common elements with earlier instruments from Kerman. One of such

instruments of 1522 is kept in Greenwich (with a later spider of the 18th century), in the National

Maritime Museum [Charette, Catalogue ..., p. 220-223], the second of 1587 - in the Museum of

the East in Moscow (unfortunately, of poor quality) [Maslikov, in production]. So we can say that

our astrolabe, although it is of late production, comes from very reputable precursors.

References:

Ackermann, S. Astrological scales on the National Maritime Museum astrolabes / S. Ackermann //

Astrolabes at Greenwich: a catalogue of the astrolabes in the National Maritime Museum.

– Greenwich. 2005. – P. 73–89.

Charette, F. Catalogue of Eastern astrolabes / F. Charette // Astrolabes at Greenwich: a catalogue

of the astrolabes in the National Maritime Museum. – Greenwich. 2005. P. 210–319.

Gibbs, S. Planispheric astrolabes from the National Museum of American History / S. Gibbs, G.

Saliba. – Washington: Smithsonian Inst. press, 1984. – 231 p. – (Smithsonian studies in

history and technology; № 45).

Maslikov, S., Sarma, S. R. A Lahore Astrolabe of 1587 at Moscow. Enigmas in its Construction /

S. Maslikov, S. R. Sarma // Indian Journal of History of Science. – 2016. – Vol. 51, Issue 3. –

P. 454–477.

Morrison, J. E. The astrolabe / J. E. Morrison. – Janus, 2007. –437 p.

Maslikov, S., Persian roots of Lahore astrolabe. In production.