March 27, 1891.] 



SCIENCE. 



179 



at such times. I am inclined to think, however, that a more 

 probable reason is to be found in the general conditions of the 

 atmosphere preceding and during the storm. It has been found 

 in our laboratory that bacteria growing on gelatine will multiply 

 with unusual rapidity during warm, sultry weather. Now, these 

 are the atmospheric conditions that usually precede and accom- 

 pany thunder-storms. It seems to me most likely, therefore, that 

 whatever rapid souring occurs is due to an unusually rapid growth 

 of bacteria, caused by especially favorable conditions of the 

 atmosphere. 



The experience of the proprietor of a neighboring creamery con- 

 firms to a certain extent these conclusions. He finds, that, if 

 milk is kept at a uniformly low temperature during the thunder- 

 storm season, no trouble results from rapid souring, indicating 

 that this souring, when it occurs, is due more to a high temperature 

 and sultry atmosphere than to the ozone in the air. If this were 

 a process of direct oxidation, it should take place, partially at 

 least, at the lower temperature. 



Professor Tolomei finds, also, that a slight electric current, if 

 less than three amperes, will have a preservative effect on milk, 

 the current being passed du-ectly through the liquid. A current 

 greater than three amperes will decompose the milk. 



In our experiments, a current of less than one-fortieth of an 

 ampere was sufficient to produce decomposition, with a certain 

 amount of coagulation at each electrode. A stronger current 

 would produce complete coagulation, with the somewhat curious 

 result that the coagulum was strongly acid at the positive pole, 

 and more feebly alkaline at the negative pole. 



Aaron L. Teeadwell. 



Wesleyaa University, 



Middletown, Conn., March 20. 



Mixed Races. 



Dr. F. von LnsCHAN, in his description of the Tachtadschy 

 (Beisen in Lykien, etc., Vienna, 1889), calls attention to the im- 

 portant fact that the Greeks of Lycia represent a mixture of two 

 distinct types, and from these facts draws the following infer- 

 ence: "At first glance, it appears remarkable and hardly proba- 

 ble that two disparate types should remain distinct, although 

 intermarriage has continued without interruption through thou- 

 sands of years. But we must acknowledge that it would be just 

 as remarkable if continued intercrossing should result in the pro- 

 duction of a middle type {Mischform). It is true that at the 

 present time the greater number of anthropologists appear to be 

 of the opinion that middle forms originate wherever two distinct 

 types live in close contact for a long time. If this is true at all, 

 it is true only in a very limited sense, and still needs to be proven. 

 A priori, we rather ought to expect that one or the other of these 

 types would soon succumb in the struggle for existence. It would 

 become extinct, and give way to the other type ; or both types 

 might continue to co-exist, although intercrossing might go on 

 for centuries. They would undergo no other changes than those 

 which each singly, uninfluenced by the other, would have under- 

 gone by the agency of physical causes." He exemplifies these 

 opinions by statistical treatment of his cranial material, and by 

 showing that in a single family all the extreme types which occur 

 among the whole people are found. 



Measurements of mixed Indian types give results which tally 

 exactly with Dr. Von Luschan's views, and tend to support Koll- 

 mann's conclusions regarding the stability of cranial forms. The 

 Bilqula (Bella Coola) of British Columbia are a mixed people, 

 their language showing that they are of Salish affinity, while they 

 have intermarried extensively with Athapascans and Haeltzukans. 

 A study of the distribution of occurrence of length width indices 

 of tljeir heads shows that the indices of from 79 to 81 are frequent, 

 those about 83 rare, those of from 85 to 87 again very frequent. 

 The first index con-esponds to the most frequent one of the Haelt- 

 zukans ; the last, to the most frequent one of the Athapascans of 

 this region. If we consider the facial indices, a similar relation 

 reveals itself. We find a greater frequency of the indices ranging 

 about 79, a few cases ranging about 83, and many about 85. The 

 height of body shows the same character of distribution, — a 



maximum about 160 centimetres, and another about 168 centime- 

 tres. If the three curves of frequency are drawn out, their cor- 

 respondence is found to be so close that it cannot be due to mere 

 accident. Other measurements do not show the same peculiarity, 

 because those of the peoples of the coast do not differ materially 

 from those of the peoples of the interior. 



When these same curves are drawn out for the Oregonian 

 Athapascans, it appears that the curves are also alike among 

 themselves, while they diflfer fundamentally from those of the 

 Bilqula. I give here a table of the length-width indices of the 

 heads of the Oregonian Athapascans, Northern Californians, and 

 crosses between the two, which will be found instructive: — 



The first column shows particularly a much slower increase than 

 we ought to expect if it represented a simple error curve; the 

 second column shows a great variability, due to the presence of 

 two distinct types. We see, notwithstanding the small number 

 of cases, the maxima of the first and of the third columns clearly 

 indicated. The asymmetry of the first column is easily explaina- 

 ble on the assumption of an intermixture with Californian tribes, 

 and that therefore the indices peculiar to them occur more fre- 

 quently. 



On studying the single cases of these groups, it appears, that, 

 although the characteristics of the component types become ap- 

 parent by a statistical treatment of the series, they do not exist 

 in the individual. The individuals are not representatives of one 

 of the parent types, but mixed types; some parts of their bodies 

 representing one type, other parts the other type. This mixture 

 appears in a great variety of combinations. Middle types, that 

 is, those standing between the two parent types, if found at all, 

 are very few in number. Feanz Boas. 



Claris University, Worcester, Mass., March 17. 



BOOK-REVIEWS. 



Outlines of Psychology. By Haeald Hoffding. Tr. by Mary E. 

 Lowndes. New York, MacmiUan. 13°. $1.50. 



The translation of this work has not been made from the original 

 Danish, but from the German translation. Professor Hoffding, 

 however, considers the German version a correct and adequate 

 representation of the original, so that English readers can here 

 obtain an accurate account of his views. The English version is 

 natural and easy, and the author's meaning is, as a rule, plain and 

 intelligible. The work is written with ability, and gives evidence 

 of prolonged study of the subject in all its departments. It opens 

 with some account of the scope and method of psychology, fol- 

 lowed by a chapter on the relations of mind and body, and then 

 takes up in succession the three fundamental elements of mental 

 life, — cognition, feeling, and will, — the first of them naturally 

 receiving the principal share of attention. The work is designed 

 as a manual for students; but for that purpose the arrangement is 

 bad, since the earlier chapters can hardly be understood without 

 some previous knowledge of both psychology and philosophy. 

 The plainness of the author's style, however, serves partly to re- 

 move this difficulty. 



As regards the substance of the work, our judgment must be 

 rather unfavorable. Professor Hoffding's philosophical standpoint 

 is that of the association school, modified somewhat by evolution- 

 ism, yet not dififering essentially from that of the EngUsh writers 

 with whom we are familiar. He attempts, indeed, to treat his 

 subject without reference to philosophical theories, stating at the 

 outset that psychology is a purely empirical science in no way 

 dependent on metaphysics; yet he is not able to adhere to this 

 position, but drops into philosophical discussion at intervals 



