KESULTS OBTAINED FOR MOISTURE. 
19 
Moisture determinations on Illinois coal (percentages). 
Details of treatment. 
Loss after 15 minutes' heating at 100° to 107° 
Additional loss after another 15 minutes' heating at 100° to 107° 
Total loss after 30 minutes' heating 
Additional loss after heating another 30 minutes at 100° to 107° 
Total loss after 1 hour's heating 
Gain in weight by standing uncovered 41 hours 
Total loss after heating another 30 minutes 
Gain in weight after standing 41 hours and reheating as compared with 
the value at the end of 1 hour's heating 
1-gram 
1-gram 
sample. 
sample. 
6.65 
8.42 
.84 
2.62 
9.26 
9.27 
.06 
.16 
9. 32 
9.43 
3.68 
3. 68 
8.86 
9.20 
.46 
.23 
2-gram 
sample. 
5.24 
3.70 
8.94 
.43 
9.37 
3.55 
9.27 
.10 
Moisture determinations on Indiana coal (percentages) 
Details of treatment. 
Loss after 30 minutes' heating at 105° 
Loss after heating another 30 minutes at 105° 
Total loss after 1 hour's heating 
Gain in weight by standing uncovered 20 hours 
Total loss after heating another hour at 105° , 
Gain in weight after 20 hours' standing and 1 hour's 
reheating compared with weight after first hour's 
heating 
Gain in weight by standing uncovered 120 hours 
Total loss after heating another hour at 105° 
Gain in weight compared with weight after the first 
hour's heating 
Gain in weight by standing uncovered 24 days 
Total loss after another hour's heating at 105°.. 
Gain in weight compared with weight after first 
hour's heating 
|-gram 
sample. 
5.50 
.04 
5.54 
3.44 
5. 20 
.34 
3.06 
4.90 
. 64 
3.70 
4. 20 
1.31 
1-gram 
sample. 
5. 60 to 5. 58 
.IJSt.) .01 
5.68 to 5.62 
3. 43 to 3. 35 
5. 45 to 5. 37 
.23 to .25 
:;. 12 to 2.95 
5. 1 1 to 5. 10 
.54 to .52 
3.62 to 3. 58 
4. 60 to L62 
1.08 to 1.00 
2-gram 
sample. 
5. 62 to 5. 61 
. 07 to . 02 
5. 69 to 5. 63 
3.41 to 3. 35 
5. 53 to 5. 48 
.16 to .15 
3. 15 to.".. II 
5. 19 to 5. 17 
.50 to .46 
3. 52 to 3. 51 
4. 72 to 4. 70 
4-gram 
sample. 
5.49 
.15 
5.64 
3.34 
5.55 
.09 
3.12 
5.21 
.43 
3.45 
1.77 
.87 
These results show that practically all of the moisture is expelled 
from coals of these kinds during the first thirty minutes, and, further- 
more, that there was an appreciable amount of oxidation in the .sample 
during standing or from reheating. For short periods this oxidation 
value in these experiments was apparently a surface reaction, depend- 
ent on the surface exposure of the sample and not on the amount. 
The samples were all weighed out in porcelain crucibles of the same 
size, and the amount of sample directly exposed was practically the 
same in all. In this case the percentage effect of equal oxidation on 
the Illinois samples would be in the ratio of 4, 2, and 1. The gains 
actually determined at the end of 41 hours were 0.46, 0.23, and 0.10 
per cent, respectively, which are very close to this ratio. 
On the Indiana sample the gains for oxidation at the end of twenty 
hours were 0.34, 0.24, 0.15, and 0.09 per cent, respectively. At the end 
of twenty-four days the percentages of gain on the different amounts 
are more nearly the same, but the gain is still greatest on the J-gram 
sample and least on the 4-gram sample, the gains on the four amounts 
taken being 1.34, 1.04, 0.95, and 0.87 per cent, respectively. 
ALTERATION OF WEIGHT OF SAMPLES OF COAL WHEN KEPT IN A 
FINELY POWDERED STATE. 
In order to investigate the question of the extent of alteration of the 
samples when kept in a finely powdered condition as prepared for 
analysis, portions of a number of such samples were put in weighed 
