Remarks on the tendency to Calculous Diseases ; with. Observations on 

 the Nature of urinary Concretions, and an Analysis of a large Part 

 of the Collection belonging to the Norfolk and Norwich Hospital. 

 By John Yelloly, M.D. F.R.S. $c. Read June 19, 1828. [Phil. 

 Trans. 1829, p. 55.] 



The account given by the author of his examination of the urinary 

 calculi contained in the Norwich Collection, the total number of 

 which is 649, relates more particularly to those which have been 

 either purposely divided, or accidentally broken in the extraction, 

 and which amount all together to about 330. He gives a tabular view 

 of the results of his analyses of these calculi, and states, in the order 

 of their occurrence from the centre, the consecutive deposits of the 

 different materials of which they are composed. About one half of 

 the specimens consist only of one description of substance, and the 

 remainder are formed of alternating layers, more or less numerous, 

 of most of the substances which enter into .the composition of human 

 urinary calculi. The distinction between the lithic acid and lithate 

 of ammonia, though generally recognised abroad, was scarcely at- 

 tended to in this country, until noticed by Dr. Prout. The lithic 

 calculi form, as is usual, the most numerous class of concretions in 

 the Norwich collection, where they amount to nearly a third of the 

 whole number ; and if the number of those containing either lithic 

 acid, or lithate of ammonia, as a nucleus, be taken into account, it 

 will appear, as already observed by Dr. Prout, that not less than two 

 thirds of all urinary calculi either consist of the lithates, or have those 

 substances as their nuclei ; whence it may be inferred, that a large 

 proportion of them probably owe their existence to the previous for- 

 mation of such a nucleus. The deposition of the phosphates is not 

 followed by that of the other materials. The oxalate of lime is the 

 only substance entering into the composition of urinary calculi, which 

 is ever found in the form of distinct and specific crystallization, and 

 it then forms what is called the Mulberry calculus. The author is 

 led from his observations to suspect that carbonate of lime, although 

 rarely found in a separate form in calculi, is not an unfrequent con- 

 comitant of phosphate of lime : with the assistance of Dr. Prout and 

 Mr. Faraday, he ascertained the presence of carbonate of lime in some 

 of the specimens which were not previously supposed to contain it. 

 This result was also confirmed by the analysis of several specimens 

 of calculi from the collection in the Hunterian Museum, and also 

 from the Museum of Guy's Hospital, which he was permitted to ex- 

 amine. 



The author is in hopes of being able to make some additions to 

 this communication, if he can obtain permission to divide some of 

 the remaining calculi in the Norwich Collection, so as to give to the 

 Society the result of the whole analysis. 



