40 
EXPERIMENTAL WORK IN FUEL TESTING. 
Determinations on sample ground to pass a 40-mesh sieve. 
First sample. 
Second sample. 
Constituent. 
Official 
method. 
Modified 
method. 
Official 
method. 
Modified 
method. 
1. 
2. 
3. 
4. 
42. 07 
10.25 
.95 
35. 72 
11.20 
44.40 
8.12 
2.71 
30.97 
Ash 
10.83 
Proximate analysis; 
« 19. 35 
«39.17 
a 30. 28 
a 11. 20 
19.35 
35.72 
' 33. 73 
11.20 
a 30. 45 
a 37. 43 
"21.29 
a 10. 83 
30.45 
30.97 
27.75 
Ash 
10.83 
100. 00 
100. 00 
100. 00 
100. 00 
a After correcting for mechanical loss of fixed carbon and ash, the difference in the fixed-carbon 
results between the two samples, due to different heat treatment, is 6.46 per cent. 
To test the effect of the fineness of grinding upon the determination 
of the volatile matter in ordinary bituminous coal, a sample of coal, 
Kentucky No. 1 C, containing 2 per cent moisture, 5.7 per cent ash, 
and 0.9 per cent sulphur, was still further reduced in ash content by 
floating on a calcium-chloride solution of 1.32 specific gravity. The 
lighter portion was then thoroughly air dried and separated by sifting 
into five sizes, and proximate analyses of the parts were made by the 
official method, with the following results: 
Determinations for volatile matter on Kentucky No. 1 C coal. 
Sizes of separation by sifting. 
Constituent. 
i to J- 
To to 5*0 
55 to jV 
4V tO B \ 
Jo and 
finer. 
Moisture 
1.15 
39.05 
58.20 
1.60 
1.45 
38.80 
58.55 
1.20 
1.70 
38.55 
58.35 
1.40 
1.90 
38.05 
58.40 
1.65 
2.05 
Volatile matter 
35.54 
Fixed carbon 
59.66 
Ash 
2.75 
By the modified process with four minutes of : _eliminary heating 
the result in volatile matter on the 'Vo to jV' size was 33.75 per cent 
and on the "g^ and finer," 32.85 per cent. 
The results in volatile matter on these different sizes are somewhat 
higher on the coarse samples. However, the different ash contents of 
the different sizes indicate that the sizing had to a degree separated 
the coal into somewhat different varieties, as the higher ash content 
of the finer sample would not in itself be sufficient to account for the 
lower volatile results. In order to see whether the difference was due 
to the fineness of grinding or difference in the coals, a portion of the 
' Vo to 3 y' sample was ground down in an agate mortar and the volatile 
matter determined on this fine portion. The average of several results 
was 37.6 per cent, as against 38.55 per cent on the coarse sample. 
From this series of results it appears, at least in low-moisture bitu- 
minous coals, that the finer ground samples give somewhat lower 
