^00 
had arrived at, for whether by process of rapid or slow 
cooling, he had found the crystals spoken of. 
Mr. West observed, that with respect to the crystaliza^ 
tion spoken of, there was little reason to believe it was caused 
by what went in at the bottom of an iron furnace. It was 
much more likely that the crystals were formed by a process 
which could be more easily conceived than described, and to 
which a name had scarcely been given. In this case a sub- 
stance descended through a very great mass of another 
material, in very small proportions, and the particles ap- 
proaching each other, most probably caused the formation of 
these crystals. He merely offered this as an opinion, for in 
the present state of their circumscribed information, it was 
impossible to arrive at any definite conclusion. 
ON THE OCCURRENCE OF SHELLS IN THE YORKSHIRE COAL 
FIELD. BY HENRY HARTOP, ESQ. 
Mr. Hartop alluded to some very interesting specimens 
of shells which had been found in the Yorkshire coal field. 
He thought he could show that some of the organic remains 
in the ironstone field had been suddenly fixed in the ironstone 
strata in which they were found, the muscles therein all being 
in a feeding position, while in another seam of ironstone, about 
100 yards deeper, an immense number of muscles were found 
with every appearance of having been floated into that posi- 
tion when dead. There were specimens from other strata 
where large fishes were found in the act of eating smaller ones. 
If they got hold of fresh water muscles alive, it would be 
generally found that they were upon their edge. He now pro- 
duced a specimen of muscles feeding, the appearance of which 
seemed to confirm the truth of the observation he had made. 
The Chairman thought the specimens looked very much 
like as if the muscles had been fed upon by other fish. 
The morning meeting then broke up. 
