NA TURE 



137 



SATURDAY, JULY 29, 1922. 

 CONTENTS. 



PAGE 



The Cause of Rickets 137 



The Border Land of Tibet and Nepal. {Illustrated.) 



By H. H. G.-A 139 



The Early Metal Ages in South America. By- 

 Henry Balfour 141 



A Monument to a Master Chemist. By Dr. E. F. 



Armstrong-, F.R.S '4^ 



American General and Economic Geology • 143 



Our Bookshelf .145 



Letters to the Editor : — 



The Intensity of X-ray Reflection.— Prof. W. L. 



Bragg, FR.S., and R. W. James . . .148 

 Geology and the Primitive State of the Earth. — 



Dr. Harold Jeffreys 148 



a-Particles as Detonators.— Dr. Horace H. Poole . 14S 

 Occurrence of a Crystalline Style in the American 

 Slipper Limpet [CrepiJula fornicaia) and its Allies. 



—Dr. J. H. Orton" 149 



Sense of Smell in Birds.— C. B. Williams . . 149 

 The Skull of Sir Thomas Browne. —Sir Arthur 



Keith, F.R.S., and Prof. Karl Pearson, F.R.S. 149 

 Bloomsbury and the University of London. (Illus- 



trated.) By T. LI. Humberstone . . . .150 

 The Physiology of Life in the Andes. [Illustrated.) 



By J. Barcroft, C.B.E., F.R.S 152 



Obituary : — 



H.S. H. Prince Albert of Monaco. By Sir W.] 



A. Herdman, F.R.S .156 



Current Topics and Events 15S 



Our Astronomical Column 160 



Research Items 161 



Leicester Conference of the Museums Association . 163 



The Arrangement and Motion of the Sidereal System 1 63 

 The Oil Palm in French West Africa . . .164 



The French Dye Industry 164 



The Metallic State 165 



University and Educational Intelligence . . . 165- 



Calendar of Industrial Pioneers 166 



Societies and Academies 167 



Editorial and Publishing Offices : 



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Editorial communications to the Editor. 



Telegraphic Address: PHUSIS, LONDON. 

 Telephone Number : GERRARD 8830. 



The Cause of Rickets. 



SO much has been, heard in recent times of rickets 

 as a disease due to a deficiency of the fat- 

 soluble vitamin A which promotes growth, that it is 

 a good corrective to examine again the position of 

 those observers who do not agree that the disease is 

 essentially an " avitaminosis," as the French would 

 say. An interesting survey of the work of the Glasgow 

 school from this point of view is given by Dr. Leonard 

 Findlay in the Lancet (April 29, 1922, vol. i. p. 8*25). 

 He there reviews the variety of investigations which 

 have been carried on for some 15 years by himself 

 and his collaborators — clinical, experimental, and 

 sociological — and comes finally to the conclusion that 

 " confinement and defective hygiene are the most 

 potent causes in the production of rickets." -While 

 opinions will differ as to whether this summary .may 

 not be too comprehensive, no one can fairly say that 

 the facts which he adduces are compatible with a 

 positive conclusion that rickets is due to a deficiency 

 of fat-soluble A. It is fortunately no longer necessary 

 to try to decide which of these two views is correct 

 for, as so often happens, it is now pretty clear that both 

 are right, and, which deserves less notice, that both 

 are wrong. The two propositions are indeed not 

 contradictory but complementary. 



In the same journal (July 1, 1922, vol. ii. p. 7) 

 appears a preliminary account by Dr. Chick and her 

 colleagues of their observations on children in Vienna 

 which goes far to reconcile and harmonise the two 

 points of view. By very careful experiments they show 

 clearly that under certain conditions rickets can be 

 Controlled by cod-liver oil, and it is legitimate to 

 assume for the present that the active factor is fat- 

 soluble vitamin A. They also show (1) that the well- 

 known seasonal prevalence of rickets in the winter 

 and early spring finds a rational explanation in the 

 preventive and curative action of sunlight, which can 

 be duplicated by rays from a mercury vapour quartz 

 lamp, and (2) that under equal conditions of diet 

 and environment the disease develops much more 

 readily in children under six months of age than in 

 those a little older, presumably in correlation with the 

 more rapid rate of growth, as Mellanby found in his 

 experiments on dogs. The occurrence of rickets is 

 evidently conditioned by a number of circumstances, 

 of which one or another may in any given case be the 

 " cause " in the pragmatical sense that attention to it 

 may give satisfactory prophylaxis or cure. 



From the vast amount of clinical and experimental 

 work on the subject which has appeared in the last two 

 or three years it seems possible to disentangle a certain 

 number of definite data. If conditions are otherwise 



NO. 2752, VOL. I io] 



