456 Chronicles of Science. [July, 



IV. CHEMISTEY. 



(Including the Proceedings of the Chemical Society.) 



Except in organic chemistry, and here only in those researches which 

 interest but the most advanced chemists, there is little of importance 

 to report. It would be wrong, however, in an English Journal to 

 pass without mention the valuable papers presented to the Eoyal So- 

 ciety by Messrs. Frankland and Duppa, " On the Acids of the Lactic 

 Series, and on the Synthesis of Butyric and Caproic Ethers from 

 Acetic Ether." No less valuable is the paper " On the Hydrocarbons 

 of the Series C„ H 2 n + 2," contributed by Mr. C. Schollemmer. All 

 these papers throw important light on the constitution of the so-called 

 organic compounds, and will be studied with much interest by all who 

 watch the wondrous development of this branch of chemistry.* 



In inorganic chemistry there are a few things of scientific and tech- 

 nical interest to which we may more particularly refer. As a curious 

 experiment and striking illustration of the play of affinities, we may 

 notice a reaction described by J. Schiel.f Into a stoppered bottle 

 filled with perfectly dry chlorine, he introduces a sealed tube contain- 

 ing peroxide of silver. He then shakes the bottle and breaks the tube, 

 and now in a few seconds finds that the bottle is filled with oxygen, 

 which the chlorine has replaced. Peroxide of silver is rather difficult 

 to produce, but the same experiment may be shown with the oxide, a 

 longer time being allowed for the displacement of the oxygen. To 

 succeed, perfectly equivalent amounts of chlorine and the oxides must 

 be employed, or the latter must be in excess. 



A new and very easy way of obtaining oxygen has been recently 

 described by Fleitmann.J He takes a clear solution of ordinary chlo- 

 ride of lime (hypochlorite) and adds to it a mere trace of freshly- 

 prepared moist peroxide of cobalt, and then heats the mixture to 70° or 

 80° C. At this temperature oxygen is freely evolved, and the whole of 

 the hypochlorite is reduced to chloride of calcium. According to the 

 author the peroxides of cobalt have a variable composition, and to 

 explain the above reaction he supposes that a lower oxide abstracts 

 oxygen from the hypochlorite to form a higher oxide, which is imme- 

 diately decomposed again into the lower oxide and oxygen. The ac- 

 tion of the oxide of cobalt is thus seen to be exactly similar to that of 

 nitric oxide in the manufacture of sulphuric acid. 



In connection with the above we may mention that Winkler ap- 

 pears to have proved the existence of cobaltic acid, Co0 3 ,§ which he 

 finds to be a very unstable body. A potash salt of the acid is obtained 

 by boiling one part of spongy cobalt with one part of caustic potash 

 dissolved in three parts of water, until a dark blue solution is pro- 

 cured. The addition of sulphuric acid to this solution liberates oxygen, 



* All the above papers will be found in the ' Proceedings of the Royal Society,' 

 vol. xv. pp. 164, 191, 198. 



t ' Aunalen der Chernie und Pharmacie,' December, 1864. 



J 11 iid., April, LS65, pp. 64. 



§ 'Journal fur prakfc. Ghemie,' vol. xc. p. 213. 



