Review of Prof. Johnson's Report on American Coals. 311 
It is greatly to be regretted that this examination did not em- 
brace all the coals, or rather all the varieties of coals, with which 
our country abounds ; and also those which our steam-ships will 
be obliged to use whilst cruising on distant stations. But no 
blame for this defect can attach to the Department under whose 
direction these experiments were made. It availed itself of all 
the means that seemed justifiable to secure so desirable an object. 
Advertisements were kept standing for months in the most prom- 
inent papers of every part of the Union, inviting mine owners and 
others to forward samples for investigation to the Navy Yard at 
Washington, where the whole operation would be conducted free 
of expense to those furnishing the samples; whilst a sufficient 
‘supply of the foreign varieties found in our markets was purchased 
for comparative trials under the direction of the Department by 
Prof. Johnson. The most important deficiency that can be found 
in this respect is in the coals from the Mississippi valley. From 
the great Illinois'and Missouri coal basin, covering an area proba- 
bly larger than the whole kingdom of France or Great Britain, 
a single sample was forwarded, whilst from that portion of the 
extensive basin of Pennsylvania, Virginia and Ohio that lies west 
of the Alleghany Mountains, an amount still less than from the 
former was obtained. Neither of these was in quantity sufficient 
to make a full series of expeyiments. We speak knowingly when 
we state, that the sample from the Illinois and Missouri basin 
(Cannelton, Ind.) was not a fair representation of the largest part 
of the coals furnished by these basins. This deficiency is much 
to be regretted ; and if the results of the examination of the other 
coals embraced in this Report, be as important to the national 
interests as we believe they are, it calls loudly for a continuance 
of these experiments in such a manner as to insure an investiga- 
tion of these western coals. 
What was done, was done thoroughly. The period occupied 
in the experiments and working up the results was about eighteen 
or twenty months. The Report covers more than 600 pages of 
congressional documéntary form, most of which is tabulated mat- 
ter. ‘The number of samples of coal experimented upon was 
forty one, viz. nine anthracite, twelve free burning or semi-bitu- 
minous, and nineteen bituminous,—to which may be added one 
sample of natural coke, two of artificial coke, two mixtures of 
anthracite and bituminous coals, and one of dry pine wood. Two 
