Intelligence and Miscellaneous Articles, 15 



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of barytes; it contains water of crystallization. The phosphovinate 

 of lead, when anhydrous, is the most insoluble of all. 



Only two of these salts were analysed by M. Pelouze ; the phos- 

 phovinate of barytes yielded, 



Phosphate of barytes 82'800 



Carbon 9*166 



Hydrogen 2-266 



Oxygen 5768 



100-000 



M. Pelouze considers the atomic constitution of this salt to be 1 

 atom of phosphoric acid saturated with 2 atoms of barytes and 2 

 atoms of alcohol, with 12 atoms of water of crystallization. The 

 phosphovinate of lead was found to be of analogous composition. 

 Phosphovinic acid is obtained by gradually adding dilute sulphuric 

 acid to an aqueous solution of phosphovinate of barytes, as long as 

 precipitation takes place. The filtered liquor is to be evaporated, 

 at first over the naked fire, and then in vacuo beside a vessel contain- 

 ing sulphuric acid. A liquid is obtained, which reduced to the con- 

 sistence of a thick oil, cannot be further concentrated ; but it does 

 not decompose at common temperatures in vacuo, as sulphovinic acid 

 does. 



Phosphovinic acid may also be obtained by decomposing phospho- 

 vinate of lead with sulphuretted hydrogen. 



The properties of phosphovinic acid are, that it has a biting and 

 very acid taste j it is inodorous and colourless, of an oily consistence, 

 and reddens the blue colour of litmus strongly. It is soluble in all 

 proportions in water, alcohol and aether, and is capable of resisting 

 long-continued ebullition when it is dissolved in several times its 

 volume of water ; but decomposes at this temperature, when at the 

 maximum of concentration, giving at first a mixture of aether and al- 

 cohol, then carburetted hydrogen, traces of oil of wine, and a residue 

 of phosphoric acid mixed with charcoal. 



Minute crystals are always formed in the concentrated solution of 

 phosphovinic acid, and in sunshine very brilliant crystals may be seen 

 to form and precipitate : the quantity of these crystals is not increased 

 by exposing the solution to cold. 



Phosphovinic acid coagulates albumen, whether it is formed by 

 the action of common phosphoric acid upon alcohol, or by phosphoric 

 acid, which has been previously heated to redness. Not the slightest 

 differences could be perceived, either in the composition or properties 

 of phosphovinic acid prepared with phosphoric and paraphosphoric 

 acid. The phosphoric acid obtained from salts, which were at first 

 supposed to be paraphosphovinates, neutralized by potash and treated 

 with nitrate of silver, always gave a yellow precipitate 3 this induced 

 1C Pelouze to suppose, though not to assert, that paraphosphoric 

 acid is not capable of forming double salts with inorganic bases and 

 alcohol, and that in acting on the last-mentioned body, the isomeric 

 property is lost. Phosphovinic acid diluted with water and put into 



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