TrcatmeiU of Calculous Disorders. '211 



symptoms that are peculiar to them, and upon the different 

 methods of treatment which they require. 



It is not necessary here to enter into the ordinary symptoms 

 of calculus of the bladder, which are so well known, and have 

 been so frequently describedj nor shall I, for obvious reasons, 

 notice the^ uncertainty and difficulty that frequently attends 

 ascertaining the situation and size, and often the existence even 

 of a calculus, by the operation of sounding. The general state 

 of the urine, and of the matters voided with it, are the principal 

 circumstances that bear upon the medico-chemical treatment of this 

 disease; and the passing of different kinds of sand, and of mucus, 

 together with the composition of the urine relatively to its healthy 

 state, are the circumstances to which we must look as those sym- 

 ptoms of the nature and progress of the malady which are chiefly 

 to guide us in its treatment. 



Considered in this view, the treatment of calculus was usually 

 pursued upon very erroneous and generally, merely upon empi- 

 rical principles, until Dr. Wollaston pointed out those differences 

 in the composition of calculi, which I have described, and which 

 were first made known by the publication of his essay in i\iQ Philo- 

 sophical Transactions for 1797. Previous to that period it was 

 customary to consider all calculi as of one kind, and soluble in 

 caustic alkalis ; these, therefore, became the prevalent remedies, 

 and have continued so even till now, under the absurd name of 

 solvents ; even at present it unfortunately happens that but little 

 of the information contained in that paper is known to, or under- 

 stood by those to whom the treatment of the cases in question is 

 usually trusted ; perhaps for want of explicit directions as to the 

 manner in which the discoveries alluded to were to be brought 

 to bear upon practice ; this was one of the main ends of those 

 papers which the Royal Society has done me ihe honour to 

 publish in their Transactions, {Phil. Trans. 1808, Sfc.) and the de- 

 ficiency has since been made good in a more able and connected 

 manner by the publication of Dr. Marcet's essay. 



When a stone has once lodged in the bladder, and increased 

 there to such a size as no longer to be capable of passing the 

 urethra, it is, I believe., generally allowed by all those who have 



