300 Scientific Intelligence. 



8. On the Inertness of Quicklime. — While the activity of cal- 

 cium oxide toward water is so well known" as to give to this sub- 

 stance the name " quicklime," yet to other substances it is in 

 general quite inert. Neither carbon dioxide nor hydrogen sul- 

 phide for example will unite with dry quicklime. Velet has 

 undertaken an investigation to determine how far the absorptive 

 power of lime for gases is dependent (1) upon the mass of water 

 present and (2) upon the temperature. In the first set of experi- 

 ments carbon dioxide was the gas employed ; in the second set 

 sulphur dioxide. The lime was contained in a tared U tube, 

 and the carefully dried gas passed over it. The amount of absorp- 

 tion was determined both by the increase of the weight of the 

 lime and by that of a soda solution placed beyond it; the sum of 

 the two giving the total mass of gas passed. It was observed 

 that the effect of a trace of water is precisely similar to that of 

 heat energy in inducing the combination of ordinarily inert sub- 

 stances. Neither carbon dioxide nor sulphur dioxide combines 

 with dry lime appreciably below 350°; these gases being quite 

 similar in this regard. At ordinary temperatures incompletely 

 hydrated lime does not combine with CG 2 ; though 10 per cent 

 of water greatly increases the absorption. Neither does ordinary 

 quicklime absorb nitrous fumes. — J. Chem. Soc, lxiii, 821, June, 

 1893. G. F. B. 



9. lecture-notes on Theoretical Chemistry. By F. C. Wkich- 

 mam, Ph.D. 12mo, pp. xiv, 225. New York, 1893 (John 

 Wiley & Sons). — In compiling this little manual the author has 

 evidently intended to offer within a small compass a general re- 

 view of "the wide domain of chemical theory" including in this 

 term not only chemical theories proper but also the physics of 

 chemistry to a large extent. Hence it contains chapters on Spe- 

 cific gravity, on Solutions, on Energy and on Thermo-, Photo- and 

 Electro-chemistry as well as chapters on Atoms and Valence, on 

 Chemical formulae, on Chemical equations and on the Periodic 

 Law. While of course these subjects can be treated only very 

 briefly within the space given them, they appear to be clearly 

 presented ; so that the student will be prepared for the more ex- 

 tended treatises, a list of which is appended. Mechanically, the 

 book is excellent. g. f. b. 



10. A Guide to Stereochemistry, based on lectures delivered at 

 Cornell University. By Arnold Eiloart, Ph.D., B.Sc. Svo, 

 pp. iv, 106. With 50 woodcuts and 5 plates. New York, 1893 

 (Alexander Wilson). This brochure is a timely resume of the 

 evolution of one of the most important subjects occupying the 

 attention of chemists at the present time. Its first 36 pages treat 

 of the Stereochemistry of Carbon and the next 14 of the Stereo- 

 chemistry of Nitrogen ; while the rest of the book is occupied 

 with an Index to the literature of Stereochemistry and a short 

 article on the use of models in teaching solid formulas. The de- 

 velopment of the subject is mainly historic. The discussion is 

 clear and, aided by the numerous illustrations, cannot fail to be 

 fully understood by the attentive student. g. f. b. 



