240 



SCIENCE. 



[N. S. Vol. V. No. 110. 



The chair was taken by Dr. McMurtrie at 

 8.15, and, after routine business had been dis- 

 posed of, the reading of papers was then taken 

 up as follows : 



' Note on an Improved Specific Gravity 

 Bottle for Liquids,' by Dr. E. R. Squibb; 

 ' Note on the Determination of Caffeine, ' by 

 G. L. Spencer ; ' Variations in the Composition 

 of Commercial Red Lead,' by Durand "Wood- 

 man ; ' The Methods for Determination of 

 Tannin,' by J. H. Yocum ; 'Modern Metal- 

 lurgy of Copper,' by J. B. F. Herreshoff". 



Mr. Spencer reviewed the precautions neces- 

 sary in the determination of caffeine by both 

 Gromberg's and the gravimetric method, and 

 concludes that the Gromberg method gives the 

 most satisfactory results, and admits of wider 

 application than the gravimetric method, par- 

 ticularly as by the latter it is difficult to obtain 

 absolutely pure caffeine. 



Dr. Woodman gave the results of a series of 

 factory tests on commercial red leads, taking 

 the position that the litharge removed by di- 

 gestion in solution of lead acetate is simply that 

 portion which has escaped oxidation, and is 

 therefore a diluent merely, and a measure of 

 the incompleteness and imperfection of the 

 roasting process. He finds no uniformity in 

 the amounts of the uncombined or free litharge, 

 either in the samples which are the subject of 

 his paper or as reported by other analysts. Ac- 

 cording to his determinations the following 

 variations are shown : 



Bed 1 5 B.W.L. 64 C. L.B. B.W.L. L.B. 



lead...51.0 41.0 60.0 28.0 58.0 90.0 73.5 87.5 

 Free 

 lith- 

 arge.. .49.0 59.0 40.0 72.0 42.010.0 26.5 12.5 



For present purposes the few per cent, of im- 

 purities were not determined, and are included, 

 some in the red lead figures, and others in the 

 litharge. 



Mr. J. B. F. Herreshoff made an address on 

 'Modern Metallurgy of Copper,' reviewing 

 briefly the historical side of the development of 

 the copper industry in this country and point- 

 ing out the remarkable increase in its con- 

 sumption, due to the advance in the appli- 

 cations of electricity. While the iron industry 



of this country is always spoken of as so enor- 

 mous, and is indeed of great magnitude, it is 

 only known to those who follow the subject 

 very closely that the production of copper 

 amounts to over one-half of the value of pig 

 iron annually produced. 



In 1895 the United States consumed 62.6 per 

 cent, of its production, but in 1896 the home 

 consumption was only about 37.5 per cent., 

 62.5 per cent, being exported. In the same time 

 there was also a large increase in production. 



Mr. Yocum reviewed the methods (and diffi- 

 culties inherent in them) of determining tannin 

 in barks and extracts. He considers a com- 

 plete extraction of tannin at low temperatures 

 as an impossibility, regardless of the amount 

 of water used. 



Durand Woodman, 



Secretary. 



THE ACADEMY OF SCIENCE OP ST. LOTTIS. 



At the meeting of the Academy of Science 

 of St. Louis on the evening of January 18, 

 1897, Professor H. S. Pritchett presented some 

 results of observations on the recent sun-spots, 

 prefacing his remarks by a general account of 

 our present knowledge of the constitution of 

 the surface of the sun, and of sun-spots in gen- 

 eral, and illustrating his remarks by the use of 

 lantern slides. 



Two persons were elected to active mem- 

 bership. 



Wm. Teelbase, 

 JBecording Secretary. 



NEW BOOKS. 



Problems and Questions in Physics. Charles 

 P. Matthews and John Shearer. New 

 York and London, The Macmillan Company. 

 Pp. vii+247. $1.60. 



The Mechanics of Pumping Machinery. Jtjlius 

 Weisbach and GusTAV Hereman. Author- 

 ized translation from the second German 

 Edition by Karl P. Dahlstrom. London 

 and New York, The Macmillan Company. 

 1897. Pp. 300. 



The Story of Extinct Civilizations. Robert E. 

 Anderson. New York, D. Appleton & Com- 

 pany. Pp. 213. 



