440 



SCIENCE. 



[N. S. Vol. VIII. No. 196. 



success. The same has been the experience 

 of other workers, notably Franke and 

 Christensen. The latter, indeed, bases an 

 argument as to the chemical character of 

 manganese on the non-existence of manga- 

 nese alums. In working with manganese, 

 O'Neal, though using apparatus similar to 

 that just described by Piccini, was not so 

 fortunate as to obtain definitely a manga- 

 nese alum, but now that it has been ob- 

 tained by Piccini there would seem to be 

 no doubt of the existence of trivalent man- 

 ganese in salts of oxy-acids. 



The cause of color in the sapphire has 

 been ascribed to various substances, but the 

 weight of authority seems to favor the 

 presence of chromium, probably in the form 

 of a lower oxid. Deville and Debray, who 

 carried out many experiments on the sub- 

 ject, are quite positive that chromium is 

 present. The effort has been made by 

 Andre Duboin to form chromium glasses of 

 a blue tint, and his results are described in 

 the Chemical News. Mixtures of silica, 

 alumina, lime and chromate of potassium 

 were heated to redness for several hours in 

 a crucible brasqued with charcoal. "With 

 this mixture only a dull blue tint was ob- 

 tained. When, however, the lime was wholly 

 or partially replaced by baryta a fine 

 blue color resulted. Jena glass and other 

 boric-acid glasses were also colored blue by 

 chromium. Calcium carbid, used instead 

 of charcoal as a reducing agent, gave blues, 

 but less fine. Of common glasses, soda 

 glass gave only a green and Bohemian 

 glass a bluish violet, but only in the vicinity 

 of the layer of charcoal. It would, there- 

 fore, seem to be quite possible that the blue 

 of sapphire is a lower oxid of chromium. 

 J. L. H. 



CURRENT NOTES ON ANTHROPOLOGY. 

 THE TRENTON ICE MAN. 



The meeting of the Anthropological Sec- 

 tion in Boston was noteworthy for the 



absence of palseolithic man. He did not at- 

 tend in person or by representative. Prob- 

 ably he modestly felt that he had been too 

 much in evidence at Toronto. But in the 

 last number of L'Anthropologie (No. 3) the 

 Marquis de Nadaillac, supported by some 

 new material furnished by Professor Put- 

 nam, says a good word for his quondam 

 existence at Trenton. 



This new evidence is the exhumation by 

 Mr. Volk of argillite chips below the ferru- 

 ginous layer in the sands. This proves, 

 reports the Marquis, that the sands above 

 and below that layer are of the same age, 

 and both glacial. 



If I read the testimony printed in Science 

 aright, it proved, indeed, that both were of 

 the same character, and that both were 

 eolian and distinctly long post-glacial. 



ANCIENT MEXICAN MIGRATIONS. 



In a recently published quarto of ninety- 

 two pages the Count de Charencey, well 

 known for his many valuable contributions 

 to American linguistics, presents a careful 

 study of the statements in Sahagun's His- 

 toiy concerning the traditional migrations 

 of the Aztecs and Toltecs. He compares 

 the old monk's account, which he no doubt 

 justly assumes was the popular tradition of 

 the time, with those of other writers, such 

 as Veitia, Tezozomoc, Ixtlilxochitl, and 

 also with the renderings of the Codices. 



The result is a critical and valuable con- 

 tribution to the subject. He does not 

 credit the interpretation of those who trace 

 the migrations across continents, but rather 

 holds that Sinaloa or Jalisco limited the 

 horizon of the tale-tellers ; though some- 

 what inconsistently, he thinks that some of 

 the narratives had an Asiatic origin (p. 34). 

 (L' Historien Sahagun et les Migrations Mexi- 

 caines. Alengon. A. Herpin, 1898.) 



THE COLOR OF THE AMERICAN INDIAN. 



In the Zeitschrift fur Ethnologie, 1898, Heft 

 2, Dr. Karl E. Kanke has an article on the 



