50 Structure of a peculiar Combustible Mineral, 
fifty diflferent specimens, as far as I know, but I can give the names of 
different coals that I tested. 
Just give us a few ? — These were Capeldrae, Wemyss, and Pirniehill, 
&c. 
Your investigations had been previously chiefly directed to the ordinary 
coals ? — Yes. 
Is it more difficult to trace the organic structure in the cannel coal than 
in the ordinary domestic coal ? — It is. 
Perhaps requires more skill and practice ? — Yes, in conducting the 
investigation into the cannel coal. 
What is the reason of that? — The reason I believe to be, that the 
structure is much more compact in the cannel coal, and the section requires 
to be made exceedingly thin, and it is very difficult to procure that con- 
dition, from the excessive brittleness of the material, and also intense 
opacity, and containing particles of hard matter, which frequently tear 
out the specimens. 
Mr. BowERBANK. — Examined hy Mr. Macfarlane. 
Mr. Bowerbank, you live in London ? — I do. 
You have given a good deal of your time and attention to microscopical 
observations ? — I have for these twenty-five years past. 
You are a fellow of the Koyal Society ? — I am. 
You were lately president of the Microscopical Society of London ? — 
I was. 
And you have written on the subject, I believe ? — I have. 
Have you made a great many examinations, with the aid of the micro- 
scope, of mineral substances ? — I have. 
Of various descriptions of coal ? — I have. For many years, the subject, 
simply as a natural-history subject, was much inquired into. 
And you have turned your attention to it ? — I have. 
And have for several years been taking observations, with the micro- 
scope, of coal substances ? — Yes. 
Have you been at Torbanehill ? — I have. 
Recently ? — Yes, recently. 
And you obtained specimens of the mineral that is working there ? — I 
did. 
And subjected them to examination ? — I have. 
Did you give a specimen last week to Professor Quekett ? — I showed 
him a specimen, and he desired to possess it for examination. 
And did you give some specimens to Dr. Adams ? — I did. 
What has been the result of your examination of coal substances ? — 
Every coal which I have examined, either by sections, or by external 
characters, or by the examination of the ash, has convinced me that it is 
an essential character of coal that it should be composed principally of 
organized vegetable substances and bitumen. 
Lord President. — Of what, did you say? — Of organized vegetable 
carbon and bitumen principally. 
Mr. Macfarlane. — With a little earthy matter ? — Yes. 
I think you said these examinations were of the sections of the sub- 
stance, and of the ash as well ? — Of the sections of the coal matter, and of 
the ash as well. The practice generally adopted in examination is, first 
to observe its ordinary characters, and next its sections, so as to develop 
its structure. 
Have you pursued the same mode of investigation in regard to the 
Torbanehill mineral?— Exactly. 
And with what result? — I have found no organic structure in it, 
