520 PANCREATIC CALCULI FROM A COW. 
I am sorry I cannot give you more information as to their 
exact seat; but, from their beautiful appearance, I have 
ventured to send you one or two as a specimen, 
And beg to remain, 
Yours, &c. 
[We thank Mr. Blakeway for the specimens he has so 
kindly forwarded us. 
There is much to interest both the chemist and the patho- 
logist in the concretions met with in various parts of the 
body, although the immediate cause in operation to bring 
about the separation of their constituents they may per- 
haps be not acquainted with. This we know, they com- 
monly consist of those principles which it is the peculiar 
function of the gland to eliminate from the organism. 
Occasionally there are deviations from this ; these, however, 
constitute the exceptions to the law. 
To the description given by Mr. Blakeway, nothing need 
be added beyond the appearance of these calculi. In size 
they are about that of peas ; in colour , a milk-white ; their 
structure is very dense ; and their surface nodulated. 
To this we may be permitted to append the following — 
URINARY CALCULI POSSESSING A METALLIC LUSTRE. 
When in Paris, M. Leblanc, Y.S., very kindly presented 
to us some cystic calculi, taken from an ox, the appearance 
of which was new to us. In form , they are spheroidal. In 
size, they vary from a pin’s head to a pea. The surface is 
smooth. In colour , they are a brilliant bronze, and appear as 
if encoated with a metallic film. On cutting through them, 
they are found to be made up of layers superposited on each 
other, and the colour is uniform throughout. 
On making a rough qualitative analysis of one of them, 
this being all that was necessary, as we knew that this had 
been carefully done by others, we found it to consist 
principally of the carbonate of lime and animal matter, with 
traces of the phosphates and of iron. And here we 
maybe permitted to notice, en passant, a circumstance which, 
about the same time, we became conversant with ; namely, — 
that if colourless glass vessels be immersed for about thirty- 
six hours in the water of the artesian well at Grenelle, they 
become covered on the surface with a similar metallic deposit. 
The inference is that the colouring principle in both is the 
same, namely, iron ; for that water is well known to be 
ferruginous and carbonated, and to the water, therefore, we 
