Remarks on Formic Acid. | 141 
It is sufficiently obvious, however, that the product must have 
been both weak and impure. With the formic acid, thus obtained, 
exists the malic acid ; and to separate the Jatter, as well as to give 
the necessary concentration, the acids were neutralized by carbonate 
of potassa, (without excess)—the malic acid then precipitated by 
acetate of lead, (added only as long as precipitation took place,) and 
the solution of the formate, thus left, when sufficiently concentrated, 
decomposed by means of sulphuric acid. Subsequently, distillation 
was necessary in order to obtain the formic acid itself; yet, even 
after this, one impurity being substituted for another, (the acetic for 
the malic acid,) it would become necessary to have recourse to the 
additional operations of combining the acids with the oxide of lead, 
and then separating their salts by well managed crystallization, be- 
fore we could obtain the formic acid free from the acetic. 
It is manifest that an acid, with so very limited a source and so 
many delays accompanying its preparation, was but ill calculated to 
excite much general interest. Even after Dobereiner had pointed 
out the mode by which it could be obtained artificially, and Wohler, 
Liebig and others, had very much extended the list of substances 
capable of yielding it by this process, there was found to exist much 
practical inconvenience, and the formic acid still continues to be 
known to many chemists, only by description. The last specimen 
which I purchased cost 50 cents per ounce, although its intrinsic 
value should not exceed 64 cents; when proper and obvious precau- 
tions are taken in its formation. 
To the taste this acid is very nearly as grateful as the best vinegar, 
and, at the same time, so very similar, that one might be substituted 
for the other by housekeepers. Most persons would certainly con- 
found them, for even the distinguished chemists, Fourcroy and Vau- 
quelin, not only deliberately published their conviction of the iden- 
tity, after an experimental inquiry which had this express object in 
view, but again asserted the same opinion when their first statement 
was opposed by the experiments of Suerson, who contended that 
the formic was a distinct and peculiar acid. The acetic and formic 
acids have an origin very similar, both coming from the same class 
bodies, viz. sugar, starch, gum, wood, &c. By a species of 
destructive distillation peculiar to each, both may be got from 
these es directly; but the acetic acid does not appear 
to winlieek an quantity of the formic, by any operations yet 
known. In addition to the evidence which H. Braconnot has given, 
that the former one is frequently generated by living vegetables, I 
