248 
ANALYSIS OF CALCULUS. 
view, and taught it in his lectures. I am, therefore, glad to be 
enabled to confirm his rf opinion. Need I say, that I should not 
have ventured thus to give publicity to the circumstance, had I 
found any mention made of it in the communications sent to 
your journal by that gentleman? and, of course, I now lay no 
claim whatever to its discovery. 
The harder parts of the calculus I find by analysis are made 
up of rather more than one-half animal matter, principally in- 
spissated mucus, and the remainder consists of the phosphates 
of magnesia and ammonia. 
An interesting inquiry arises as to the kind of oat most likely 
to cause an accumulation of this substance, and also what pre- 
ventive and curative means, if there are any, should be had 
recourse to. 
ON THE MEDICINAL AGENCY OF THE HYDRO- 
CYANIC ACID. 
By Mr. Hayes, of Rochdale. 
In my case of phrenitis, in the January number of The Ve- 
terinarian, I stated that I believed prussic acid had a con- 
siderable effect on spasmodic action of the heart ; and I also 
stated my intention of shewing its value by cases wherein I had 
tried it, and with the best results. I will, therefore, endeavour 
to redeem my pledge, by simply relating a few cases as they 
stand in my notes taken at that time. But before I proceed, 
allow me to state, that in the one in the January number there 
is an error committed, either by my pen or the printer. The 
dose of acid is there stated as three drops : it should have been 
thirteen, if it was Gay Lussac’s ; but if Scheele’s, I give forty ; 
if Magendie’s, thirty : I have used all these, but principally that 
of Magendie. 
CASE I. 
August \th, 1826. — I was desired to see a fine half-bred horse, 
six years old, and sixteen hands high, belonging to Mr. Garner, 
a farmer near Altrencham. I found him labouring under violent 
tetanus, with visibly strong convulsive action of the heart, and 
the jaws completely set ; he had been docked eleven days pre- 
viously. It was as severe a case of tetanus as ever I saw, with 
spasmodic action of the heart conjoined. I bled to 12 lbs., and 
got aloes in solut. 3 viij, with antim. tart. 3 j, nitr.3ij, digitalis 3 iss 
