Observations on Mr. Brande's Paper on Calculi. 239 



might therefore be expected ; but even then the nucleus of 

 uric acid would remain, and thus a great deal of time would 

 be lost without any permanent advantage. 



I have also occasionally remarked, that during the use of 

 acids, the uric acid reappears, and even seems to be aug- 

 mented in quantity. 



Attempts have been made at different time3 to effect the 

 solution of calculi, by the injection of solvents into the blad- 

 der. This subject has been more lately revived by Fourcroy 

 and Vauquelin, who, in their paper on the composition of 

 calculi, lay down rules for its practice. Independent, how- 

 ever of the impossibility of ascertaining the composition of 

 the calculus with sufficient accuracy, it is obvious that, were 

 the composition of the surface of the calculus known, the 

 frequent introduction of an instrument into the bladder, and 

 the long continuance of the process which would be neces- 

 sary, even where the calculi are small, are insurmountable 

 objections ; and whenever this mode of treatment has been 

 adopted, it has speedily been relinquished, as it always ag- 

 gravates the sufferings of the patient. 



It has been shown that in the majority of cases, the nuclei 

 of calculi originate in the kidneys, and that of these nuclei 

 by far the greater number consist of uric acid ; the good 

 effects therefore so frequently observed during the use of an 

 alkali, arise, not from any actual solution of calculous mat- 

 ter, but from the power which it possesses of 'diminishing 

 the secretion of uric acid, and thus preventing the enlarge- 

 ment of the calculus, so that, while of a very small form, 

 it may be voided by the urethra. 



XXXVI. Some Observations on Mr. Brande's Paper on 

 Calculi. By Everard Hox\ie, Esq., F.R.S.* 



-L hat calculi in the human bladder are not dissolved by the 

 internal, use of alkaline medicin.s, is an opinion which I 

 have long entertaiued, but the grounds of failure so clearly 

 pointed out by Mr. W. Brande, were not known to me : I 



* From Philosophical Transactions for 1838. Part II. 



onlv 



