1822.] Philosophical Transactions for 1822, Part I. 373 
which, under such circumstances, the stomach was exposed, from 
the time of the division of the nerves, to the influence of a vol- 
taic battery sent through the lower portion of the divided nerves, 
its contents were apparently as much changed as they would have 
been in the same time in the healthy animal. The change was also 
of the same kind, the contents of the stomach assuming a dark 
colour, and those of the pyloric end being more uniform, and of 
a firmer consistence than those of the central and cardiac por- 
tions of the stomach; while the whole contents became less in 
quantity.” 
ILL. On some Alvine Concretions found in the Colon of a Young 
Man in Lancashire, after Death. By J. G. Children, Esq. FRS. 
&e. &c. (Communicated by the Society for Promoting Animal 
Chemistry.) 
An abstract of this paper has already been given in the Annals 
for January last, p- 75, but we may add the following particu- 
lars: The concretions were found lodged in the arch of the 
colon, the coats of which were much thickened and formed into 
a sort of pouch, where they lay. The peritoneum was but little 
inflamed, the other viscera were healthy. The unfortunate sub- 
ject of the paper never took a single repast without oatmeal in 
some shape or other, and the concretions consist of alternating 
concentric layers of a velvety fibrous substance from the inner 
coat enveloping the farina of the oat, and of phosphate of lime, 
together with the ammoniaco-magnesian phosphate. 
LV. On the Concentric Adjustment of a Triple Object Glass. 
By William Hyde Wollaston, MD. VPRS. 
Dr. Wollaston here describes a method of correcting the 
central adjustment of a triple object-glass which appears not to 
have been used for that purpose, but for the details of which we 
must refer our readers to the paper itself, as they would be use- 
less without the accompanying plate. The principle and its 
result are explained as follows : 
“When any bright object is viewed through a glass of this 
construction, without an eye-glass, there may be observed at the 
same time with the refracted image, a series of fainter images, 
that are found by two reflections from the different surfaces ; 
and as the position of each of these images is dependent on the 
curvatures of that pair of surfaces by which it is formed, they 
appear at different distances from the object glass. Since the 
number of surfaces is six, the number of binary combinations of 
these surfaces is 15; and just so many images formed by reflec- 
tion may be discerned. It is manifest, thatif the glasses be duly 
adjusted to each other, so that their axes are correctly coinci~ 
dent, then this series of images must be all situated in the same 
straight line ; and conversely, that any defective position may 
be immediately detected by a derangement of the line of 
images.” 
“ By these guides alone, I have now so repeatedly restored 
