II. RESEARCH. 591 



2432. Series of Cryohydrates. Frederick Guthrie. 



These are solutions of various salts in water, of such strengths that, when 

 reduced below O C. to the temperature marked on each flask, the salt and 

 the water solidify together at that temperature. The same bodies in all 

 cases result from the mixture of the respective salt with ice as a freezing 

 mixture. 



2433. Graphic Diagram, showing (1) the solubility of ice 

 in the cryohydrates of various salts, (2) the composition of the 

 cryohydrates and their melting points, (3) the solubility of the 

 anhydrous salts in the cryohydrates and in water, (4) the temper- 

 ature which the salt produces when used in a freezing mixture 

 witli ice or as an ice cryogen. Frederick Guthrie. 



2435. Nitroxide of Amylen. Frederick Guthrie. 



Discovered by the exhibitor. Of historical interest as being the first 

 instance in which peroxide of nitrogen NO 2 was shown to behave as a 

 halogen in uniting directly with an define to form a body homologous with 

 " Dutch liquid." The composition of the body is C 5 H 10 2NO 2 . 



2436. Sulphide of (Enanthyl. Frederick Guthrie. 



Discovered by the exhibitor, and of historical interest as being the first 

 instance in which a term of a higher alcohol series was made from terms of 

 lower alcohols. Formed by the action of zinc ethyl on sulpho-chloride of 

 amylen. 



2437. Nitrite of Amyl. Frederick Guthrie. 



Discovered by M. Balard. Its therapeutic action discovered, and its 

 introduction into the pharmacopoeia recommended, by the exhibitor. Now 

 coming into use in tetanic and other nervous affections. 



2438. Collection of Preparations relating to chemical 

 history of podocarpic acid (Annalen der Chemie und Pharmacie, 

 vol. 170, p. 213). Prof. A. C. Oudemans, Delft. 



2439. Hydrocarbons and Derivatives from Pennsylvania 

 Petroleum. 23 specimens. C. Schorlemmer, F.R.S. 



Group I. Normal Paraffins. 

 Pentane. Pentene. Pentyl chlorides. 



Hexane. Hexene. Hexyl chlorides. Hexyl acetates. Hexyl alcohols. 

 Heptane. Heptene. Heptyl chlorides. Heptyl alcohols. Octane. 

 Group II. Isoparaffins. 



Isopentane. Isohexane. Isoheptane. 

 Group III. Aromatic Nitro-compounds. 

 Dinitrobenzene. Dinitrotoluene, 

 Nitro-compounds from fraction 



boiling at 110 120 

 120 130 



130 140 solid and liquid. 

 140 150. 



2440. Ethyl-Compounds, derived from dimethyl, which was 

 obtained by the electrolysis of potassium acetate. Four speci- 

 mens. W. H. Darling. 



Ethyl chloride. Ethyl alcohol. Dichlorethane. Sodium Acetate. 



