22 - History of physical Science from [July, 



of nitric acid in the liquid. As the evaporation goes on oxide 

 of antimony precipitates, and no butter is obtained. This incon- 

 venience is obviated by adding a quantity of muriatic acid, and 

 then continuing the evaporation. The nitric acid is decomposed, 

 chlorine is formed, and when the liquid is evaporated to dryness 

 butter of antimony is readily obtained. — (Ann. de Chim. et de 

 Phys. iv. 165.) 



VII. ACIDS. 



1. Sorbic Acid. — Mr. Donovan's discovery of this acid has 

 been confirmed by the subsequent experiments of Braconnot and 

 Vauquelin, of which an analysis will be given in a subsequent 

 number. 



2. New Method of procuring Chloric Acid. — Mr. James Lowe 

 Wheeler informs us that chlorate of potash may be decomposed, 

 and chloric acid obtained in a state of purity by the following 

 process : Mix a solution of chlorate of potash with an excess of 

 fluosihcic acid prepared by causing water to absorb the fluo- 

 silicic acid gas till a pretty concentrated solution of it is 

 obtained. Both liquids should be warm. Fluosilicate of potash 

 is precipitated abundantly in a gelatinous state. Filter and 

 saturate the liquid by means of carbonate of barytes. The 

 chlorate of barytes may now be obtained in crystals. These 

 crystals are to be dissolved in water, and the barytes precipitated 

 by the cautious addition of sulphuric acid, according to the 

 method employed by Gay-Lussac for obtaining chloric acid. — 

 (Royal Institution Journal, iv. 287.) 



3. Union of Hydriodic Acid with the two Phosphureted Hy- 

 drogens. — M. Houton Labillardiere has observed, that hydriodic 

 acid gas is capable of uniting with its own volume of protophos- 

 phureted hydrogen gas. The two gases condense each other, 

 and form cubic crystals of a white colour, which are volatilized 

 by a gentle heat. This compound is decomposed by exposure to 

 the air, by water, by alcohol, and by most of the salifiable bases, 

 the protophosphureted hydrogen being evolved. 



Common phosphureted hydrogen (viz. the gas composed of an 

 atom of hydrogen and an atom of phosphorus) likewise combines 

 with hydriodic acid gas. One volume of this gas unites with 

 two volumes of the acid gas. When this combination is decom- 

 posed, protophosphureted hydrogen gas is evolved, and phos- 

 phorus precipitated. — (Ann. de Chim. et de Phys. vi. 304.) 



4. ISleto Acid formed by the slow Combustion of Ether. — Sir 

 H. Davy observed that when a hot platinum Avire is plunged into 

 a vessel filled with a mixture of common air and the vapour of 

 ether, the wire becomes red hot, and continues luminous till the 

 whole of the ether is consumed. During this slow combustion 

 of ether, a peculiar acid is formed, which is recognized by a 

 particular odour which it exhales. Mr. Faraday made some 

 experiments upon this acid ; but as he was unable to obtain it 



