66 



NA rURE 



[July 14, 1923 



Research Items. 



Cancer in the United States. — The incidence 

 of cancer in the United States is discussed by Dr. F. 

 Hoffman in an article in the World's Health for 

 May, p. 18. In the general registration area, the 

 cancer death-rate has increased from 74*4 in 191 1 to 

 83*4 in 1920 per 100,000 population, but in some of 

 the individual States is much higher, and, making 

 all allowances, the conclusion is that cancer is seriously 

 on the increase. A dangerous phase of the cancer 

 problem is that alleged cancer cures are gaining in 

 popularity, with results disastrous in the end. Dr. 

 Hoffman states that having personally investigated 

 the incidence of cancer among Indian tribes in the 

 south-west and in Bolivia, he is satisfied that malig- 

 nant disease in any form, and particularly cancer of 

 the breast, is extremely rare. 



The Teeth of Piltdown Man. — In the American 

 Journal of Physical Anthropology (vol. vi., April- 

 June), Dr. Ale§. Hrdlicka publishes an important 

 contribution to the study of the phylogeny of man in 

 a paper on the dimensions of the first and second 

 molars, and their bearing on the Piltdown jaw. Dr. 

 Hrdlicka has subjected to a detailed analysis the 

 recorded measurements of these two molars in man, 

 and has made a careful examination of the material 

 in the U.S. National Museum. As a result, his con- 

 clusions are that the Piltdown molars are longer and 

 have a lower index than any group of modern men ; 

 as compared with early man they exceed in length all 

 prehistoric molars except one or two first molars 

 from Krapina, and, with one exception, present the 

 lowest breadth-index ; in breadth they are ordinarily 

 human. When compared with the apes it is clear 

 that they do not belong to this group, though 

 nearest in proportion to the gorilla. Of the fossil 

 apes, the teeth most closely resembling the Piltdown 

 teeth are those of Dryopithecus rhenanus, Pohlig, of 

 the Bohnerz Alb. Dr. Hrdlicka's general conclusion 

 is that the Piltdown teeth, primitive as they are, 

 belong to very early man or to his very near precursor, 

 while he suggests that the resemblance to the late 

 Miocene or early Pliocene fiu man-like teeth of the 

 Bohnerz Alb. m.ay legitimately raise the question 

 whether man may not have evolved altogether in 

 Western Europe. 



Human Sacrifice as a Rain Charm in Northern 

 Rhodesia. — In January last a report appeared in 

 the Times which stated that eighty natives had been 

 arrested in Rhodesia for complicity in a case of 

 human sacrifice due to witchcraft. This report was 

 of peculiar interest in view of the fact that the natives 

 of this region, which lies about forty -five miles beyond 

 Mount Darwin, just on the boundary of Portuguese 

 territory, are noted for their addiction to witchcraft 

 in a form which presents some remarkable parallels to 

 the traditional rites and practices of European witches. 

 From the evidence given at the trial, of which an 

 account is given in the Times of June 26, it would 

 appear that in this instance it was not a case of 

 witchcraft in the generally accepted sense. The 

 sacrifice was offered by the Mtawara tribe to pro- 

 pitiate Mwari, the Great Spirit of the tribe, and thus 

 bring to an end a drought which threatened the tribe 

 with disaster. Mwari has two waves. One came 

 some generations ago from a branch of the tribe 

 living in what is now Portuguese territory and was 

 domiciled within a circle of trees, presumably a sacred 

 grove. This wife, Mashongavudzi, is an old woman, 

 past child-bearing, whose husband is dead. At her 

 death her place is taken bv another old woman who 

 assumes the same name. The second wife, Nechiskwa, 



NO. 2802, VOL. I 12"! 



is chosen from the family of Gosa, the chief of the 

 branch of the tribe in Portuguese territory, when a 

 child — the present holder of the office is about nine 

 years old — and must remain a virgin throughout- her 

 life. She is the Rain Goddess. When there is a 

 drought Gosa .sends an offering of limbo (coloured 

 cotton print) to the Mwari, which is placed near the 

 throne of the Rain Goddess. If rain fails to follow, 

 Mwari is angry because some one has seduced his 

 wife. The only remedy is that the culprit should be 

 sacrificed by fire. In this case suspicion fell on a 

 son of the chief who is in charge of the wives of 

 Mwari — an office which has descended to him from 

 his ancestors. The accused man was duly offered up 

 as a sacrifice by burning and, curiously enough, rain 

 followed in twenty-four hours. 



Kata-thermometer Studies. — Dr. Leonard Hill's 

 campaign against the stagnant, warm atmospheres 

 which are encouraged by many of the modern plans 

 of warming and ventilating buildings is steadily 

 gaining the success it deserves. Cool moving air 

 and local radiant heat mean a cool head and warm 

 feet, which is the ideal state for human comfort and 

 efficiency. The stimulating qualities of an atmo- 

 sphere depend on its temperature, humidity, and 

 movement, and in the kata-thermometer Dr. Hill 

 introduced an instrument which gives directly a 

 measure of the cooling and evaporative powers of 

 the air ; i.e. the properties which through their 

 action on the skin determine the pleasantness for 

 man. " The Kata-thermometer in studies of body 

 heat and efficiency " (Medical Research Council 

 Special Report Series, No. 73, 1923) gives a mass of 

 data collected by Dr. Hill, Dr. H. M. Vernon, and 

 others, under a variety of conditions ranging from 

 boot and shoe factories to imitations of shipwrecked 

 sailors in the wind tunnel at Hampstead. There is 

 also a discussion of the theory and practice of the 

 instrument and a description of a recording apparatus 

 designed by Dr. E. H. J. Schuster. The section on 

 the relation of general metabolism to kata-thermo- 

 meter readings raises a question of considerable 

 importance to which no answer seems to be yet 

 available. Atmospheres which are " good " by Dr. 

 Hill's standard increase metabolism, and more food 

 is needed and desired. Riding on the top of a bus, 

 for example, instead of inside, means, as he points 

 out, a greater expenditure on food. It is also gener- 

 ally agreed that it promotes general healthiness 

 and vigour. But why is it that a high rate of meta- 

 bolism is better for the body than a low rate ? The 

 effect may be essentially psychological, but the point 

 requires discussion. The whole report will well repay 

 detailed examination. 



Tsetse Flies. — The April issue of the Bulletin 

 of Entomological Research contains a report of 

 Drs. W. B. Johnson and L. Lloyd on tsetse fly 

 investigation in the northern provinces of Nigeria. 

 The authors bring forward evidence showing that 

 sleeping sickness can appear and become epidemic 

 in localities where the only tsetse carrier present is 

 the species Glossina tachinoides, and it is at least 

 probable that this insect is responsible for the disease 

 in certain localities where it abounds and the usual 

 carrier G. palpalis is rare, or wanting. Both G. 

 palpalis and G. tachinoides suck the blood to a 

 considerable extent of the non-mammalian fauna — 

 probably that of reptiles. The two species can 

 tlirive where the wild fauna is reduced to its possible 

 minimum, and G. tachinoides where man is almost 

 the only available host. The authors anticipate that 



