CHEMICAL REPORT.



might probably be excluded as belonging rather to the bitumin-
ous shales than coals,) was 46.32 per cent. The average ash
percentage of the cannel coals examined, excluding No. 2291,
was 9.36: varying from 2.20 per cent. in No. 2369, Letcher
county, to i9.50 in No. 238i, of Morgan county. It will be
seen by reference to the table that several of the Kentucky
cannel coals are more than equal in gas-making or gas-improv-
ing power, to the cannel coal of West Virginia, which is much
used for that purpose.
  The specific gravity of the coals, here reported, varies from
i.i9i in No. 2354, of Letcher, with an ash percentage of only
2.60, to 1.634 in No. 2286, in Carter, with an ash percentage of
40.00. This latter, however, should more properly be called a
bituminous shale than a coal. It is proposed to draw the line
between these shales and coals proper on the ash percentage of
20.00, giving the name shale to all which have a greater per-
centage than this.
  The volatile combustible matters of these coals (excluding the
cannel coals) varies from 22.70 per cent. in No. 2346, from
Letcher, which had an ash percentage of 9.54, to 40.90 per
cent. in No. 2354, of Letcher, which had an ash percentage of
only 2.60.
  Thefixed carbon in the coke varied from 33.76 per cent. in
No. 2381, of Morgan county, to 67.60 per cent. in No. 2404, of
Pike.
  The sulphur varied from 4.527 per cent. in No. 2385, from
Morgan county, to 0.390 per cent. in No. 2405, of Pike county.
  Those coals which have the largest proportion of fixed carbon
with the smallest percentage of sulphur are the best fitted for
coking purposes, provided they have enough volatile combustible
matters to cause them to soften and become porous in coking,
and to afford heat enough by their combustion to effect the pro-
cess without burning fixed carbon.
  Cannel coals do not make good coke for the iron-smelting
furnace, because, although they give more volatile combustible
matter than most other coals, they do not soften much or become
porous in coking. The so-called bituminous or soft coals, gen-
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