176 Miscellaneous Intelligence. 



9. Effect of Muriatic and Sulphuric Acid on Hydrocyanic Acid. — 

 It is well known that hydrocyanic acid may sometimes be preserved 

 for years unaltered, and, at other times, changes and undergoes 

 decomposition in eight or ten days after its preparation. Whilst 

 searching for the causes which influenced the spontaneous change 

 of the acid, M. Kuhlman examined into the action occasioned by 

 mixing other acids with the hydrocyanic compound. A mixture 

 of muriatic and prussic acids being made and set aside, in twelve 

 hours the bottle containing it was lined inside with yellow cubical 

 crystals ; some were less coloured than others, and those formed 

 after a longer interval of time were colourless. The fluid part re- 

 mained limpid, but was diminished to one half. The experiment 

 was repeated with recently prepared prussic acid, mixed with its 

 bulk of muriatic acid. No yellow crystals were obtained, but a 

 large quantity of colourless ones, similar to those last obtained with 

 the former liquor. With the exception of the colouring matter of 

 the first crystals (apparently depending upon the smaller quantity 

 of muriatic acid in that experiment), they all appeared to consist of 

 muriate ofammonia only. No gas was evolved by the mixture and 

 action of the acids. 



Equal parts of sulphuric and prussic acids were then mixed, 

 though with some little difficulty. A slight elevation of temperature 

 took place : after two days, no crystals were formed, no colour 

 produced, no gas evolved. Heat being then applied, a little prussic 

 acid was volatilized, but that soon ceased ; much inflammable gas, 

 probably carburetted hydrogen, was formed, and the colourless li- 

 quid, on cooling, became a crystalline mass of transparent needles, 

 easily recognized to be sulphate of ammonia. — Ann. de Chimie, 

 xl. 441. 



10. Phosphorus in Vacuo. — The following experiment is men- 

 tioned by Berzelius as due to Van Bemmeleer : — Sprinkle a stick 

 of phosphorus here and there with resin and sulphur, put it under 

 the receiver of an air-pump and exhaust : the phosphorus will be- 

 come more luminous at the parts powdered than on the other parts, 

 and ultimately inflame. 



11. On the composition of Phosphuretted Hydrogen, by M. Buff. 

 — The analyses of the two compounds of hydrogen and phosphorus, 

 performed by MM. Dumas and Rose, not agreeing, M. Gay Lussac 

 requested M. Buff to repeat in his laboratory the experiments of 

 M. Dumas. 



i. Proto-phosyhuretted Hydrogen. 

 The gas which was subjected to the following experiments was 

 prepared with phosphoric acid. It did not inflame in air, and dis- 

 solved in sulphate of copper without leaving the least residue. 

 Decomposed in curved bell-glasses by antimony and zinc, it con- 

 stantly yielded, for 100 parts, 1 50 of hydrogen. Potassium presented 



