XVI. Some Observations on Mr. Brande’s Paper on Calculi. 
By Everard Home, Esq. F.R.S. 
Read May 19, 1808. 
i hat calculi in the human bladder are not dissolved by the 
internal use of alkaline medicines, is an opinion which I have 
long entertained, but the grounds of failure so clearly pointed 
out by Mr. W. Brande, were not known to me : I only 
know from experience, that, to whatever extent the medi- 
cines are given, no such effect takes place. The circumstance 
of the exterior laminae of calculi extracted from patients, 
who had persevered in a course of alkaline preparations, 
having been found softer than the parts towards the centre, 
has always been considered as a proof of the action of the 
medicines upon the calculus, and led to the belief, that where 
the stone was small, it might be wholly dissolved. This, 
however, Mr. W. Brande has now proved to be a deception, 
and that the soft part is not a portion of the original calculus, 
but a newly formed substance, in which the uric acid is not 
deposited in crystals, but mechanically mixed with the phos- 
phates, and the animal mucus in the urine. 
Having met with cases, which confirm Mr. W. Brande’s 
observations, it will be satisfactory to state them, as they may 
assist in doing away many erroneous notions generally enter- 
tained on this subject. 
