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phasize the necessity of testing fuel, it the best
practicable results and greatest economies, in one
of the most salient factors of operating costs, are
to be realized, and with the relation of fuel costs
to other items of transportation expense, the difference
in heat units in different fuels, and the
difference in physical character of fuels in mind,
no railroad, which has not already done so, can
afford to continue the use of fuel now purchased
for a given territory without making a systematic
investigation to determine the fuel most efficient
for use and which will best serve the interest of
the railroad company as a whole. It would be
unjust not to mention, at this time, the excellent
work which has been done, along this line, by the
United States Geological Survey and later by the
Bureau of Mines in making laboratory tests, including
the proximate analysis, calorimetric determinations
and ultimate analysis.
To determine the fuel best to use on a given
lailroad. it is first advisable, by means of laboratory
determinations of approximate analysis,
calorific value, etc., to determine the relative
quality and efficiency of all the fuel either on the
lines of the railroad company or tributary to same.
With this information and a map of the railroad,
showing various divisional points, before yon, a
territorial classification of the fuel can readily
be made and with the general traffic conditions,
original cost of the fuel and cost of hauling in
mind, it should not be difficult to determine, within
reasonable limits, the most practical and economic
fuel for use in a given territory and at all times,
traffic conditions permitting, the
QUALITY' OF THE FUEL
should take precedence over favorable geographical
location.
The recommended method of sampling coal both
in the mine and in car lots is the method outlined
by the United States Geological Survey as follows:
Mine samples should be taken in a number of
places at widely separated points in the mine
where the coal bed has an average development.
It is preferable to determine these locations by
an examination of the mine map before going into
the mine. At each of the places designated the
face of the coal should be cleared of burnt powder,
loose coal or dirt for about 5 feet in width and
the full height of the wormable seam. All insecure
places in the roof should also be taken down
to prevent tlieir falling into the sample. The
sampler should then spread a waterproof blanket
on the floor of the mine close up to the face of the
coal and make a perpendicular cut, with a mine
pick, from the floor to the roof, including in the
sample everything but the parts of the coal bed
which are originally discarded by the miner.
Sufficient coal should be cut to make a volume
equal to not less than live pounds to the foot in
THE COAL TRADE BULLETIN. 53
height, that is, a sample weighing not less than
20 pounds should be cut from a four-foot, bed of
coal. When shale or other partings aie to be
included in the sample care should be exercised
to cut them Ibe full width and depth of the groove
in order to preserve the proper proportion of coal
and extraneous matter. When the required amount
of coal has been obtained, detailed measurement
of the section of tlie bed, from top to bottom, noting
every perceptible parting and variation in the
seam, should be made. The parts of the bed not
included in the sample
SHOULD HE CLEARLY SHOWN
in the record. The cuttings should then be sifted
through a screen with a i^-inch mesh, the lumps
broken to a size that will admit of their passing
ihiough a (..-inch opening. The samples should
then be mixed by two men grasping opposite corners
of the blanket, rolling the sample diagonally
by raising one corner of the blanket at a time, a
further thorough mixing effected by hand. When
the sample is thoroughly mixed, and all impurities
are evenly distributed throughout the mass,
the sample should be quartered and the two opposite
quarters discarded. The remainder should
then he mixed as before, continuing the quartering
and discarding process until the sample is
sufficiently small for convenient handling. The
material finally remaining should then be spread
in a circular mass about two inches thick on the
blanket, a small trowel used to fill a sample can,
taking portions from the circumference to the center
of the mass, and around the entire circle. The
can should then be closed, neimetically sealed and
sent to the laboratory.
The entire process of sampling should be carried
on as rapidly as possible at the places in the mine
where the sample was cut and the maximum time
allowed for cutting, mixing and taking" sample
should not exceed one hour. All material encountered
in cutting across the face of the bed
should be included in the sample except partings
or binders more than three-eighths of an inch in
thickness and lenses or concretions of sulphur or
other impurities greater than two inches in maximum
diameter and one-half inch in thickness. If
the sample is taken from a very wet place it
should be taken out of the mine and dried until all
sensible moisture has been driven off.
When samples are taken from cars they should
not be limited to a few shovelfuls of
COAL FROM THE TOP
of the car. because the heavier pieces gradually
work down toward the bottom; samples taken at
the bottom of the car have shown as much as 8
per cent, more ash than the coal at the top, the
moisture also frequently varying from top to bottom
depending on the weather. In order to get
a fair car sample it is necessary to take a number