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at Prague a health centre from which the infectionof true hygiene may radiate out into lands whereplague centres are the rule. We hope the LittleEntente, as the understanding between Roumania,Hungary, and Czecho-Slovakia has been termed,has included in its understanding a concerted

Icampaign against epidemic disease.

Rickets and Vitamins.IN the April number of the British Journal of

Expe’rimental Pathology Professor D. NOËL PATONand Mr. A. WATSON, after a brief recapitulation oftheir previous work on the subject, give a detailedaccount of further experimental investigations intothe aatiology of rickets in pups. They use through-out pups from the same litters for comparativetests, as, in their opinion, the susceptibility ofdifferent strains is so varied as to invalidatestatistics collected except on this principle. ’The object of the first of the new series of experi-

ments recorded has been to test the possibilityof rearing dogs free from rickets, when confinedin a laboratory, on diets : (1) rich in milk-fats,and (2) poor in fats supposed to contain an anti-rachitic factor. Both sets of pups developed rickets,but those on an abundant diet less rapidly. Inorder to ascertain whether this delay could beattributed to a decrease in susceptibility dueto more ample energy intake, apart from theinfluence of any accessory food factor associatedwith milk-fat, a second series of experimentswas undertaken. Pups from three litters weredivided into four classes, in each of whichthe energy intake was kept ample throughoutthe whole period of growth mainly from one

of the following sources : (A) Whole fresh milkand bread (2 pups); (B) whole dried milk andbread (3 pups); (C) separated milk, bread and lard(4 pups); (D) separated milk and bread (9 pups).Two of the pups in Class D were kept in a largekennel with an open yard, and were freely exercisedevery day; and in order to try and hasten the onsetof rickets two others, also in Class D, were keptin a rabbit hutch from the age of 12 weeks tothe age of 16 weeks. The rest were kept in a

laboratory, a large sunny room with a concretefloor, in movable pens measuring 5A ft. square.Very special precautions were taken to ensurecleanliness. Of these pups, one, in Class B, died atthe end of the ninth week of the diet, not fromrickets. One only, in Class D, of the remainderdeveloped rickets. The conclusions drawn fromthese experiments by the authors are as follows :-

(1) In young dogs under ordinary laboratory con-ditions a liberal allowance of milk-fat, up to even

14 g. daily per kilo of body-weight, does not prevent theonset of rickets.

(2) Pups kept largely in the open air may escape thedevelopment of rickets on an intake of less than 1 g.of milk-fat per kilo of body-weight.

(3) With scrupulous care as to cleanliness it is, atleast sometimes, possible to rear pups free of rickets inthe laboratory on an intake of only about 0’5 g. ofmilk-fat per kilo of body-weight, along with bread,provided that the diet affords an adequate supply ofenergy.

(4) The energy value of the diet, however supplied,quite apart from the presence of any hypothetical anti-rachitic factor in milk-fat, would seem to play a part incontrolling the development of rickets ; but that it isonly a contributory part is shown by the developmentof rickets in pups with a high energy intake if con-fined in the laboratory without scrupulous care as tocleanliness.

(5) Milk-fat may be reduced to about 0’3 g. per kiloof body-weight, if its place is taken by an equal amountof lard, without the onset of rickets.

(6) The results of these observations give no supportto the conclusion of the Accessory Food Factors Com-mittee of the Medical Research Council that rickets is adeficiency disease due to a lack of an antirachitic

factor in the diet.Much work on accessory food factors has been donesince the publication in 1919 of the report referredto. With more knowledge distinctions have becomeless absolute. For example, Professor E.MELI.JANBY,1referring to the observations of HESS and UNGER,emphasises the difference in distribution of thefat-soluble factor and the so-called antirachiticfactor in vegetable fats. He says that thoughcotton-seed oil is generally accepted as contain-

ing no fat-soluble A, in his experience it isone of the better vegetable oils in preventingrickets. And investigators are by no means agreedeven on the presence or absence of fat-soluble Ain any given foodstuff. Professor PATON, followingmost authorities, assumes that lard is consideredvitamin-free, while quite recent work by Dr. J. C.DRUMIvIOND2 differentiates between lard derivedfrom grass-fed pigs and those fed on a dietdeficient in vitamins. In the former he has foundfat soluble A. Incidentally Professor PATON deducesfrom the first experiment quoted above that forexperimental purposes " dried milk may safely besubstituted for fresh milk." Dr. DRUMMOND classestheir relative content of fat-soluble A as ++ and- f--E---. Since quantitative results that cannotbe expressed numerically are of doubtful value,not even the firmest adherents of the vitaminhypothesis could regard this as an important con-tribution to the question of the form in whichmilk ought to be supplied to children. We onlymention it as a further sign of what an enormousmass of work yet remains to be done before the

presence or absence of a vitamin from any food-stuffs, still less the aetiology of rickets, can beproved. In fact, those who are inclined to be quitebewildered by the conflicting results of differenteminent observers in the same field can derivesome help from a critical essay by T. B. OSBORNEand L. B. MENDEL.3 These authors draw attentionto the contradictions existing in the literature as tothe presence or absence of a fat-soluble vitaminin a given experimental diet, and are inclined toattribute the discordant results of various workersto traces of this vitamin in certain dietsgenerally considered free from them. However,they agree with Professor PATON in emphasisingthat the crucial experiment in which nutritivefailure ensues immediately upon giving a dietdeficient in this respect has not yet been done.They might have gone even further. Until a moreaccurate quantitative basis of estimating vitamincontent can be attained the question must remainunsolved. ——————

1 THE LANCET, 1920, i., 857.2 Maternity and Child Welfare, May, 1921.

3 Jour. Biol. Chem., 1921, 45, 277.

LONDON INTER-COLLEGIATE SCHOLARSHIPS BOARD.-Seventeen medical entrance scholarships and exhibitionsof an aggregate total value of about JE1580 will be offered forcompetition on Tuesday, June 28th. These are tenable inthe faculty of medical sciences of University College andKing’s College, and in the medical schools of WestminsterHospital, King’s College Hospital, University College Hos-pital, the London (Royal Free Hospital) School of Medicinefor Women, and the London Hospital. Particulars may beobtained from the secretary of the Board, S. C. Ranner,M.A., the Medical School, King’s College Hospital, DenmarkHill, London, S.E. 5.