November 25, 1922] 



NA TURE 



7i 



Research Items. 



Pottery-making on the Blue Nile. — In Sudan 

 Notes and Records, April-July, 1922, Mr. H. A. 

 Macmichael contributes a report, illustrated by 

 sketches, of pottery-making on the Blue Nile. The 

 vessels of which the manufacture is described are the 

 Burma or pots for carrying and storing water, and 

 the water-jars used for the Sagias or water-wheels. 

 The implements used are a roughly smoothed lump of 

 stone the size and shape of a penny bun, and an 

 oblong, slightly concave, river shell, which, if un- 

 procurable, can be replaced by a fragment of dry 

 water-melon husk. With these the lump of clay is 

 kneaded with donkey's dung, is beaten into shape, 

 and smoothed. The industry of making the Sagia 

 jars is not originally found in the Sudan, but is rather 

 Nubian and riverain. 



Immigrant Groups in America. — In the Scientific 

 Monthly for November, Prof. Kimball Young discusses 

 the results of applying intelligence tests to various 

 immigrant groups in America. He points out that 

 whereas up to the year 1882 the highest percentage 

 of immigrants came from the British Isles and 

 Northern and Western Europe, of recent years a 

 complete change has taken place, the highest 

 percentage now being from Southern and Eastern 

 Europe. This change, he considers, is of the greatest 

 importance for the future of America. If the more 

 recent additions to America are of a less intelligent 

 stock than the earlier inhabitants, then the con- 

 sequences will be serious for the future. In order to 

 test intelligence, the writer used the already well- 

 known American Army tests, modified to suit the 

 children he was testing, and he also considered the 

 work of others studying racial differences by like 

 methods. As a result of a very careful study he 

 brings forward evidence to show that the intelligence 

 of these Southern European stocks is very much 

 lower than that of the other stocks. If that is so, 

 then the continued dilution of the original, more 

 intelligent, stocks by these inferior ones will seriously 

 affect the average intelligence of the population of 

 the country. As a practical deduction, it is urged 

 that there must be a complete change in public 

 opinion on the desirability of large numbers of 

 immigrants ; and secondly, that immigration must 

 be controlled in the interests of the national welfare, 

 new-comers not being allowed to enter unless they 

 can read a certain standard in intelligence tests. 



New Antarctic Brittle-Stars. — The Ophiuroids 

 collected by the Australasian Antarctic Expedition 

 (1911-1914), under the leadership of Sir Douglas 

 Mawson, are the subject of a memoir by Prof. R. 

 Koehler, of Lyons, illustrated by 15 quarto plates, 

 crowded (indeed over-crowded) with excellent photo- 

 graphs by the author (Sydney: John Spence. 

 Price 1 os. Sd.) There are 37 species, of which 

 19 are new, and three of the latter serve as 

 types of three new genera — Ophiosparte and Ophio- 

 daces among the Ophiacanthidas, and Ophioceres, 

 which is intermediate between Ophiolepis and 

 Ophioplocus in the Ophiolepididae. Ophioripa also 

 appears to be a new generic name, unless, indeed, 

 Prof. Koehler's report on the Ophiuroids collected 

 off the Philippines by the Albatross was published 

 before this one. Some nine species previously known 

 from the Antarctic or sub-Antarctic have their 

 horizontal and bathymetric limits considerably 

 extended. Asteronyx loveni and Homalophiura 

 irrorata, being now found in the Antarctic, may 

 claim to be absolutely cosmopolitan species. The 

 latter was dredged at a depth of 1800 fathoms along 



NO. 2769, VOL. I IO] 



with a new Astrodia and Ophiomusium planum, 

 which last was previously known from great depths 

 in the Atlantic and Indian Oceans. When so much 

 is added to our knowledge from only fourteen stations, 

 we realise how much there must be still to learn. 

 We may, however, hope that the number of recent 

 ophiuroid genera will not be greatly increased. 



" Insulin " and the Oxidation of Sugar. — The 

 experiments of Von Mehring and Minkovski in 1889 

 showed that in the absence of the " Islets of Langer- 

 hans " of the pancreas, sugar was imperfectly utilised 

 by dogs, thus leading to the condition known as 

 diabetes mellitus. An internal secretion was natur- 

 ally supposed to be responsible, but extracts of the 

 pancreas were found to have little or no capacity 

 of replacing the islet tissue. It seems that some 

 constituent of the whole pancreas, perhaps trypsin, 

 destroys the internal secretion. It occurred to Dr. 

 Banting of London, Ontario, that if use were made 

 of glands in which the ordinary secreting tissue had 

 degenerated as a result of tying the duct, this destruc- 

 tion might not occur. Accordingly, arrangements 

 were made by which Banting, in conjunction with 

 a group of workers in Prof. Macleod's laboratory 

 at Toronto, investigated the question. The results 

 have been published in a series of papers in the 

 Trans. Roy. Soc. of Canada, the Amer. Journ. of 

 Physiology, and elsewhere, under the names of Banting, 

 Best, Macleod, Collip, and others. Active extracts 

 were obtained in the way mentioned, and finally 

 a method was discovered by which they could be got 

 from ordinary pancreas, by the use of alcohol, in a 

 form suitable for hypodermic injection. The pre- 

 paration has been named " insulin." It has the 

 properties of increasing the consumption of sugar 

 by the tissues and indirectly that of fat, which is 

 incompletely burned in the absence of the oxidation 

 of sugar. The concentration of sugar in the blood, 

 both of normal and of diabetic animals, is thus reduced. 

 That it is burned is shown by the rise of the ratio 

 between the carbon dioxide expired and the oxygen 

 taken in, as also by direct experiments on the excised 

 heart. The toxic effects of the products of incomplete 

 oxidation of fat disappear. An important new fact 

 is that the blood sugar of normal animals can be 

 reduced to a low level, and when this is reached 

 various abnormal symptoms appear, especially in 

 the nervous system. In the rabbit, attacks of con- 

 vulsions finally lead to death. All these results can 

 be abolished immediately by giving glucose. In- 

 sulin is also effective in diabetes in man, but repeated 

 injections are necessary since the effect of one dose 

 lasts only about twelve hours, and each individual 

 dose must not be so large as to bring about the low 

 level of blood sugar above mentioned. 



Visibility as a Sign of coming Rain. — Excep- 

 tional visibility as a sign of coming rain is discussed 

 in the Meteorological Magazine for October from 

 observations made by Mr. W. H. Pick of the Meteoro- 

 logical Office, Air Ministry, at Cranwell, Lincoln. 

 Observations were taken on 518 days from April 1, 

 1920, to August 31, 1921. Visibility is observed 

 hourly, and the classification of a day with visibility 

 of 21 miles or more is a day on which such visibility 

 was observed at one or more of the hours from 9 h. 

 to 17 h., and similarly with a visibility of 13 miles, 

 the latter being naturally included in the visibility 

 of 21 miles or more. The days with ram between 

 the period of visibility and 7 h. on the following 

 morning are also tabulated. An examination of the 

 data is said to show that, so far as Cranwell is concerned, 



