TENDENCY TO CALCULOUS DISEASES. 
69 
Part II . — Of Urinary Concretions. 
When I proposed an examination of the urinary calculi belonging to the 
Norfolk and Norwich Hospital, I had the expectation, that my attention would 
have been materially circumscribed by the previous labours of Dr. Marcet, 
who visited Norwich some years before, for the express purpose of examining 
the collection. I found, however, that none of the calculi contained in it were 
divided, and that the experiments instituted by our lamented colleague (of 
which an account was published in his work on Calculous Diseases,) were 
therefore necessarily confined to the outer surface, except in cases where the 
calculus had been broken in the extraction, and its interior structure thus 
allowed to be seen. 
Within the last four or five years, a certain portion of the calculi have 
been divided ; and these, as well as such as were broken in the extraction, 
amounting together to about 330, I have carefully analysed. 
I wish I could have extended the examination over the whole collection, 
which consists of 649 specimens* ; but as there is no very speedy prospect of 
the remainder being divided, so as to admit of a satisfactory analysis being 
made of them, I am unwilling, longer, to defer laying before the Society the 
results of my examinations, which exhibit a more extensive series of observations 
in this part of pathological chemistry, than has yet, as far as I know, been pre- 
sented from any cabinet in this country. I shall be happy in embracing a fu- 
ture opportunity, of going through the whole remaining part of this splendid 
collection, should the division of the residue be effected within a convenient 
period. At the same time, however, it is not likely, that the proportions of the 
different descriptions of calculi which form the remainder, will differ materially 
from that of the large portion which I have analysed. — I have put the results 
of the analysis in a tabular form ; and have stated, in the order of their occur- 
rence from the centre, the consecutive deposits of the different materials of 
which the calculi are composed, according to the most prominent character of 
such material. I have said nothing of mixed calculi, or of calculi consisting, in 
the same apparent deposit, of mixtures of different ingredients ; because it is 
* This was the number up to the end of the year 1827. During the year 1828, there has been an 
addition of 11 specimens to the collection, from the occurrence of that number of operations. 
