REMOVING THEM, IN DO.VESTIC ANIMALS. B7o 
a calculus taken from the urethra of a pig, which, in its compo¬ 
sition, much resembles those which are found in the human 
subject. The external surface, presenting a beautiful white crys¬ 
tallized appearance, was composed of a triple salt—the phosphate 
of magnesia and ammonia ; the interior, a dark brown portion, 
also in a crystallized state, w'as composed of uric acid in combi¬ 
nation with these phosphates. It thus appears that the pig, 
like man, being an omnivorous animal, has consequently a greater 
variety of chemical combinations in its calculi, than herbivorous 
animals.” 
At the time when this paper was written, it was supposed that 
a complete cure had been effected, and the mare for some consi¬ 
derable time did her work; but the symptoms ultimately recurred, 
and she was at length destroyed. The following account of her 
has been transmitted to me b}’ Mr. Pope, and which does him 
the highest credit as a skilful practitioner and an honest man ;— 
Dear Sir, Tarves, October 2d, 1832. 
Permit me to trouble you with the concluding part 
of the case which I first communicated to you about a twelve¬ 
month back, ‘^a case of urinary calculus in a work-mare,” and 
which was publicly reported as having been successfully treated. 
W e were, unfortunately, too sanguine in our expectations as to 
the final result; and candour and justice compel me to relate to 
you the concluding history of the case; and, if you think fit, you 
are welcome, so far as I am concerned, to lay it before the public. 
I have sometimes wished that other practitioners would favour 
us with an account of the health and condition of their patients 
a twelvemonth after their report of some supposed extraordinary 
cure. 
‘You are aware that when I returned to the country here after 
attending your lectures I found the mare nearly about as ill as 
ever. I then made an examination of the bladder; there was no 
new stone formed, but the urine was mixed with sand. I need 
not repeat the symptoms here, as I mentioned them in my former 
communication. By the advice of your assistant, I tried what 
effect muriatic acid might have upon the urinary secretion ; but, 
as the mare could not drink her water when the acid was mixed 
with it, and finding it difficult otherwise to administer it, I was 
obliged, after some time, to give it up. 
* I can hardly say that it produced any sensible effects: at times 
the urinary discharges would become less frequent, and, in con¬ 
sequence, the excoriations on the inside of the thighs would heal 
up; but this was also partly the case when no medicine was 
given. 
