May 29, 1896.] 



SCIENCE. 



821 



sulphocyanides, giving the results of the investi- 

 gations of Liebig, Lowig, Cahours, Medlock, 

 Henry, Pelouze, Schmidt, Keimer and Upper- 

 Tcamp. The last work on the series was done 

 twenty-one years ago. 



Normal heptyl sulphocyanid is a colorless, 

 mobile liquid, having a slightly alliaceous but 

 rather pleasant odor and a specific gravity of 

 0.931 at 15 degrees C. 



Dr. Austen exhibited an apparatus for lecture 

 demonstration of the properties of the heavier 



Wm. McMurtkib, 

 Secretary pro tern. 



CHEMICAL SOCIETY OF WASHINGTON. 



The eighty-seventh regular meeting was held 

 Thursday, March 12, 1896, with the Presi- 

 dent, Dr. de Schweinitz, in the chair. There 

 were 35 members present, and Dr. Andrew 

 Stewart was elected to membership. Mr. F. P. 

 Dewey read a paper on ' The Refining of Lixi- 

 vating Sulphides.' Dr. Dewey's paper re- 

 viewed the leaching process and the treatment 

 of the sulphide precipitates produced. He de- 

 scribed the sulphuric acid process of treating 

 the sulphides, in which they are treated in 

 strong sulphuric acid to convert the sulphides 

 into sulphates, after which the charge is treated 

 with water, the silver precipitated by copper 

 and melted, and the copper sulphate crystal- 

 lized. 



Prof. H. W. Wiley and E. E. Ewell read 

 a paper on ' The Determination of Lactose in 

 Milks by Double Dilution and Polarization.' 

 They called attention to the arbitrary correction 

 proposed by Wiley in the determination of lac- 

 tose in milk in a paper published in Vol. 6, 

 page 289, of the American Chemical Journal. 

 This arbitrary factor had been found too small, 

 and the object of the present investigation was 

 to eliminate it altogether, and to determine the 

 degree of the correction to be made for the 

 volume of the precipitate in each case by 

 double dilution and polarization. The method 

 was worked out carefully on whole milk, 

 skimmed milk and cream, and it was found 

 that the correction for the volume of the pre- 

 cipitate should be determined in each particular 

 instance, as it varied from less than three cubic 



centimeters in skim milk to more than seven- 

 teen cubic centimeters in cream for 100 cubic 

 centimeter flask. Citations were given to 

 other papers in which objection was made to 

 the optical method of determining lactose by 

 rpason of the fact that a dextrin oid body was 

 sometimes found in milk, but the danger of 

 error arising from this source is not great. 



Prof. H. Carrington Bolton read a paper on 

 ' Berthelot's Contributions to the History of 

 Chemistry. ' He reviewed his ' Collection des 

 Alchimistes Grecs ' (Paris, 1887; 3 Vols. 4to), 

 and his ' La Chimie an Moyen Age ' (Paris, 

 1893 ; 3 Vols. 4to), showing their scope, analyz- 

 ing their contents, and indicating the important 

 changes in chemical histoiy resulting from 

 Berthelot's studies. He also described briefly 

 the character of the Greek papyri of Leyden, 

 as well as the Arabic, Syriac and early Latin 

 manuscripts. The origin of alchemical ideas 

 concerning the transmutation of metals is at- 

 tributed by Berthelot to attempts of Egyptian 

 goldsmiths to make alloys which fraudulently 

 imitated the precious metals. The Latin works 

 said to be translated from the Arabic of Geber 

 are shown to be fictitious, yet genuine writings 

 of Geber are extant. The technology of the 

 writers of the third to the twelfth century is 

 disclosed in the volumes received. 



The topic of discussion for the evening was 

 ' Style in Chemical Books and Papers.' Dr. 

 Wiley opened the discussion and was fol- 

 lowed by Prof. Bolton, Prof. Seaman, Prof. 

 Clarke, Prof. Munroe, Mr. Fireman and Dr. de 

 Schweinitz. 



A. C. Peale, 



Secretary. 



BIOLOGICAL SOCIETY OF WASHINGTON, 26IST 

 MEETING, SATURDAY, MAY 2. 



L. O. Howard exhibited a picture of three 

 young ladies, triplets, giving statistics on the 

 subject of triplets and stating that it was very 

 rare for all three to reach maturity. Frederick 

 V. Coville exhibited a ball 3J inches iu di- 

 ameter, taken from the intestine of a horse. 

 It was of a light brown color and felt-like con- 

 sistency and was composed of the barbed hairs 

 of the crimson clover, Trifolium incarnatum. 

 When over-ripe crimson clover hay is fed to 



