THE LACTATES, AND UREA AS IT EXISTS IN URINE 149 
ways given me the same results, which has led me to con- 
clude, thatthe white opaque amber should be preferred by 
pharmaciens to every othervariety of the samefossil resin, 1st, 
because its powder is more acrid, and consequently more active 
when employed in fumigations; 2d, that it is more soluble in 
rectified alcohol, and the tincture obtained being more charg- 
ed with matter, must equally have greater strength ; 3d, that 
this variety ought also to be preferred to obtain succinic acid, 
because it gives double the quantity of the ordinary kind ; 4, 
lastly, that the white opaque kind ought to produce a larger 
quantity of the acid, and to have an acid taste more marked 
than all the other varieties of amber. 
Journ. de Chimie Medicale. 
ART. XXVI. — RESEARCHES ON THE LACTATES, AND ON 
THE STATE IN WHICH UREA EXISTS IN THE URINE OF 
MAN, AND SOME OTHER ANIMALS. By MM. Cap and Henry. 
I. Having, during the last year, been required to analyse 
an anomalous, viscous urine, we remarked, among other 
circumstances, a much smaller proportion of lactic acid and of 
urea than is usual in ordinary urine. The remarkable proper- 
ties of urea, and more especially those of lactic acid, caused us to 
imagine that, in this instance, the morbid state of the urine 
and its organic secretory apparatus, might depend upon the ab- 
sence of these two principles, and we presumed, by their arti- 
ficial combination, a new therapeutic agent would be obtained, 
which might be useful in analogous affections. Such were the 
motives and objects of the researches which form the subject 
of this essay. 
The existence of lactic acid, which was long considered 
doubtful, has been positively established by the recent labors 
of MM. Pelouze and Jules Gay Lussac. The presence of this 
