November 0, 1903.] 



SCIENCE. 



603 



This style of charge was then tested with a 

 quantity of ores containing sulphur combined 

 with iron, copper, zinc and lead. The charge 

 for the final assay was ore 1/2 assay ton, 

 litharge TO grams, soda 15 grams. Niter as 

 calculated for a 20-gram button (from the re- 

 sults of the preliminary assay). The buttons 

 were soft, malleable and weighed from 17-23 

 grams, while the results' in gold and silver 

 were slightly higher than the old methods and 

 the loss in the slag slightly less. 



The Influence of Diet, Muscular Exertion and 

 Loss of Sleep upon the Formation of Uric 

 Acid: H. C. Sherman. 



Observations made in connection with me- 

 tabolism experiments upon three professional 

 athletes and one subject of sedentary habits 

 showed the quantity of uric acid eliminated 

 to be primarily dependent upon the quantity 

 of meat products in the diet, and to be in- 

 fluenced very little, if any, by the abundance 

 of a bread and milk diet, by a considerable 

 loss of sleep, or (in the case of the professional 

 athletes) by long-continued muscular exertion. 

 With the subject of sedentary habits, a much 

 smaller amount of exercise increased slightly 

 the uric acid elimination. This paper will 

 appear in the November issue of the Journal 

 of the American Chemical Society. 



H. C. Sherman, 



Secretary. 



ELISHA MITCHELL SCIENTIFIC SOCIETY. 



At the 150th meeting of the Elisha Mitchell 

 Scientific Society, held in the Chemical Lec- 

 ture Room of Person Hall, University of 

 North Carolina, October 13, the following 

 papers were presented: 



The Use of the Vector Diacjram in Electrical 

 Engineering : Mr. J. E. Latta. 



Tanning (with specimens) : Professor Charles 



Baskerville. 



After outlining modern methods of tanning, 

 especially by the use of chromium nitrite, a 

 number of rare skins which had been done 

 for Messrs. TifiFany & Co., of New York, were 

 exhibited. The skins were presented to the 

 Museum of the Chemical Laboratory. 



The Influence of the Spermatozoon on the 

 Larval Development of the Sea-Urchin ; Pro- 

 fessor H. V. Wilson. 



A New Indicator: Professors E. V. Howell 



and A. S. Wheeler. 



A new indicator extracted from the hulls 

 of the muscadine or wild Bullaee grape was 

 announced. This coloring matter gives a red 

 color with acids and green with alkalies, being 

 purple in neutral solutions. The only solvents 

 so far found which may be used for its extrac- 

 tion are alcohol and water. It responds to 

 inorganic and organic acids and volatile and 

 non-volatile alkalies. Carbon dioxide does not 

 affect it. 



On adjournment of the public session, the 

 annual meeting was held for the election of 

 officers and transaction of business. The pro- 

 posed agreement with the North Carolina 

 Academy of Science was approved. By this 

 agreement the Journal of the Mitchell So- 

 ciety becomes the official organ of the North 

 Carolina Academy of Science, its size being 

 doubled and issued quarterly. The following 

 officers were elected for the ensuing year: 



President — Professor Charles Baskerville. 



Vice-President — Mr. J. E. Latta. 



Recording Secretary — Professor A. S. Wheeler. 



President Venable retains the permanent 

 secretaryship. Charles Baskeraille, 



Secretary. 



DISCUSSIOX .4iVD CORRESPOyDEXCE. 

 A iiitiierto undescribed visual phenomenon. 



To the Editor op Science : The phenomenon 

 of apparent movement described by Dr. Gould 

 (Science, XVIIL, 536) was discussed in 1896 

 by Professor S. Exner in an article entitled 

 'TJeber autokinetische Empfindungen' (Zeits. f. 

 Psych, u. Physiol, d. Sinnesorgane, XIL, 313). 

 According to Exner, the first obsen-ation on 

 record was made by Alexander von Humboldt 

 in 1799. Several authors (among them men 

 as well known as Aubert and Charpentier) 

 have occupied themselves with the phenom- 

 enon ; and it forms the subject of an experi- 

 ment in Sanford's Laboratory Course, 1898, 

 309. 



E. B. TrrcHENER. 



