Chemistry and Chemical Arts. 129 
By distilling the formate with sulphuric acid, previously diluted with 
its weight of water, a pure and very concentrated ‘formic acid i is 
obtained, whose odor is acid and pungent.—Jdem. 
4. Phosphovinic Acid, by Peiovzr. (Ann de Ch. t. 52, p. 37.) 
Phosphoric acid in reacting upon alcohol, gives origin to this acid, 
which is formed of one atom of phosphoric acid and two atoms 
of alcohol. In order to prepare it, concentrated alcohol is mixed 
with phosphoric acid in a syrupy consistence, nearly in equal parts. 
The mixture is maintained for some minutes at a temperature of 60 
or 80°C. ; at the end of twenty four hours, it is diluted with seven or 
eight times its volume of water, and neutralized with pulverized car- 
bonate of baryta. The liquid is raised to ebullition in order to expel 
the excess of alcohol. It is then left to cool to 70° C., filtered and 
suffered to remain for crystallization, when the phosphovinate of ba- 
ryta crystallizes in beautiful, hexagonal tables, or scales. These are 
dissolved in water, and sulphuric acid is added to the solution, grad- 
ually, so long as a precipitate is occasioned; the liquid is filtered, 
concentrated at first to a certain point over a naked fire, and after- 
wards im vacuo with the aid of sulphuric acid, until it is reduced to 
a syrupy consistency. The acid has a gelatinous consistency ; it is 
very acid, without odor, soluble in every proportion in water, alco- 
hol and ether, capable of resisting perfectly a prolonged ebullition, 
when dissolved in several times its volume of water; decomposing, 
on the contrary, at this heat when in a concentrated state, and yield- 
ing at first a mixture of alcohol and ether, afterwards of carburetted 
hydrogen, and a residuum of phosphoric acid mingled with charcoal. 
It dissolves zinc and iron with the disengagement of hydrogen, and 
expels the carbonic acid of all the carbonates. 
e phosphovinates are infinitely more fixed than the sulphovi- 
nates ; they support a heat capable of inflaming wood; they change 
into neetril phosphates by calcination. The most of them are so- 
luble in water. Those which do dissolve in this liquid, dissolve in 
the feeble acids. The salts of the protoxide of tin, of mercury, of 
silver, of lead, and of lime are the least soluble. The phosphovinate 
of baryta has a saline and bitter taste. It is much more soluble at 
40° than at 0° and at 100°C. It is insoluble in alcohol and ether. 
It contains 0.306 of water, or 12atoms. It loses this by calcination 
and becomes pearly white, but is not decomposed except in a dull 
Vou. XXVIII.—No. 1. 17 
