576 
DR. PROUT ON ANIMAL CHEMISTRY. 
or the formation of oxalic acid. Some of these are remarkable 
and very characteristic. In the first place, the formation of oxa¬ 
late of lime in the shape of urinary calculus, may be mentioned as 
one of the most usual and obvious; and it has been principally by 
close attention to the phenomena and symptoms usually accom¬ 
panying this form of concretion, that I have been gradually led 
to the little knowledge I possess on this subject. One very im¬ 
portant class of affections, frequently connected with the forma¬ 
tion of oxalic acid, are certain skm diseases; these, from slight 
scaly crusts, down through every intermediate stage, to boil, car¬ 
buncle, and even malignant forms of disease, as fungus hse- 
matodes, often accompany a tendency to saccharine diseases, 
either in the shape of sugar or oxalic acid, or more frequently 
both. When, in particular, the oxalic diathesis prevails, it is rare 
not to find the skin more or less affected, either in the shape of 
scaly spots on the arms or legs; or troublesome boils, which, in 
advanced life and more inveterate forms of the affection, some¬ 
times assume the shape of carbuncles. I have several times seen 
impetiginous affections accompanied by a temporary saccharine 
condition of the urine, and, after this has disappeared, succeeded 
by malignant disease of the bladder, of the kind usually termed 
fungus hsematodes. Even in those cases in which there is not 
actual disease, when oxalic acid is generated in the system to 
much extent, the skin often assumes a peculiar character difficult 
to describe, and a livid tint mixed more or less with green or yel¬ 
low ; and the venous blood is often of an unusually dark colour. 
Together with this state of things there is generally extreme 
nervous depression or irritability, accompanied by flatulency (aris¬ 
ing from the extrication of immense quantities of azote), irregular 
action of the heart, and a state of mind almost bordering on in¬ 
sanity. And in those predisposed, any thing producing great 
nervous depression, or anxiety, seems sometimes capable of in¬ 
ducing the affection; certainly, at least, of much aggravating it, 
when it already exists. There is one variety of phthisis connected 
with affections of the saccharine radical, and it invariably proves 
the most irremediably fatal. When large calculi of the oxalate of 
lime exist in the kidneys, they are very apt to be accompanied by 
organic disease, and the blood voided with the urine is generally 
of a very dark or greenish colour. If our time permitted, several 
other curious circumstances connected with the present subject 
might be pointed at; but I hasten to consider another set of dis¬ 
eases connected with derangements of the saccharine radical; 
namely, the formation of acetic acid. 
One of the most frequent diseases connected with the formation 
of acetic acid is a variety of the fever usually termed hectic. The 
