CALCULI IN THE SHEATH AND URETHRA OF A DONKEY, 217 
smaller size, and gradually became larger by molecular ag¬ 
gregation. The penis was very much retracted within its 
sheath, and could with difficulty be brought forward, and 
when it was, to my astonishment I found the two smaller 
calculi in the urethral canal, as well as another about the size 
of a large pea, which I am sorry to say is lost. Upon the 
whole of these being removed, a large quantity of urine 
was voided, and the animal became free from pain. Two 
sutures were passed into the wound, and a diffusable stimu¬ 
lant was given. The wound was subsequently treated in 
the ordinary manner. 
The day after the operation the sheath was considerably 
swollen ; to which warm fomentations were therefore applied. 
The animal appeared easy, and ate cut grass with avidity; 
on which food he was kept until discharged. 
The second day he appeared to be just the same, excepting 
that a healthy flow of pus had taken place from the 
wound. 
The fifth day the swelling had decreased ; union of the 
edges of the wound had taken place ; the health of the animal 
had greatly improved, and he continued to do well until 
discharged, which was on the tenth day after the operation. 
About a monthafterwards I saw the owner,who said that the 
animal was better in health than he had been for a long period 
prior to the operation as he then was constantly having, what 
he thought to be attacks of colic, but these, no doubt arose 
from pain and irritation caused by the presence of the calculi, 
which must have been some time forming. 
ANALYSIS OP THE CALCULI. 
[The weight of the largest of these concretions is giij 5ij; 
its shape that of an imperfect cone ; its colour light grey ; 
its surface smooth; and smell highly urinous. 
A section being made of it, it was found to be made up 
of layers superposited upon each other, and alternating to¬ 
wards a common centre, which consisted of an aggregation 
of small crystals. 
A fragment under the blow-pipe blackened, exhaling 
the odour of animal matter. The flame being urged it 
became white, and lost half its weight. In dilute hydro¬ 
chloric acid this underwent perfect solution, with much 
effervescence, and from the solution oxalate of ammonia 
threw down an abundant white precipitate. 
A portion unburnt similarly conducted itself in dilute acid, 
but a quantity of flocculent matter subsided, which under the 
xxxiii. 29 
