62 
SELECTED ARTICLES. 
ART. XI. — PRODUCTS RESULTING FROM THE ACTION OF 
NITRIC ACID UPON AMIDINE. By M. Pelouze. 
M. Braconnot, some years since, made known an action 
of concentrated nitric acid, by which many substances, espe- 
cially amidine and lignin, are converted into a new matter, 
which he denominated xyloi'dine; but the composition of this 
substance, and the circumstances accompanying its formation, 
were not examined. The present paper has for its object the 
elucidation, in part, of these points. 
If nitric acid, of the specific gravity of 1.5, be mixed with, 
or poured upon amidine, this latter disappears completely in 
the course of a few minutes; the solution, treated with water, 
lets fall the whole xyloi'dine, and after filtration and evapora- 
tion, leaves scarcely any residue. 
If, instead of producing the precipitate by means of water, 
immediately after the amidine is dissolved, the liquid is set 
aside in a closed vessel, it becomes gradually colored, and 
assumes the various tints of a mixture of nitric acid and 
deutoxide of nitrogen. Water forms with it a precipitate, 
which diminishes with the increase of time; at the end of 
two days, and sometimes even in a few hours, the liquid 
ceases entirely to become even cloudy; the xyloi'dine has 
been destroyed, and converted completely into a new acid, 
which, by evaporation, is presented under the form of a solid, 
white mass, uncrystallizable and deliquescent, and of which the 
weight is much greater than that of the amidine submitted to 
the experiment. Moreover, neither carbonic or oxalic acid 
is produced during this reaction. 
The xyloi'dine, the first product of the action of nitric acid 
upon amidine, is the result of the union of the two substances. 
It is common amidine in which one atom of water is replaced 
by one atom of nitric acid. The whole amidine is changed 
into this substance, which perfectly explains the considerable 
augmentation of weight observed when the xyloi'dine is pre- 
cipitated by water immediately after the amidine has disap- 
