22 
EXPERIMENTAL WORK IN FUEL TESTING. 
Without exception these samples all increased in weight upon stand- 
ing. At the same time the moisture values usually decreased. The 
gain in weight is to be ascribed to oxidation, and the decrease in 
moisture either to actual loss or to fixation of a portion of the mois- 
ture present by the oxidation changes. If the moisture loss be con- 
sidered as an actual escape of moisture from the sample, the total gain 
due to oxidation is equal to the observed gain plus an amount equal to 
this moisture loss. The table below gives the total oxidation changes 
considered on this basis, together with the original and final calorim- 
eter determinations on some of the samples, also the loss in calorific 
value in excess of that due merely to changes in weight of the sample. 
For purposes of comparison the amounts of moisture, ash, and sul- 
phur present in the sample are also given. 
Determinations of oxidation, calorific value, moisture, ash, and sulphur. 
[Minus sign denotes loss.J 
Sample of coal. 
Increase 
in 
weight 
due to 
oxida- 
tion. 
Calorific value. 
Moisture. 
Ash. 
Labo- 
ratory 
num- 
ber. 
Field number. 
Original. 
Final. 
Gain or 
loss 
above 
that ac- 
counted 
for by 
oxida- 
tion. 
Sulphur. 
Illinois No. 9 A 
Illinois No. 9 B 
do 
Pi r '■(nl. 
1.68 
1.78 
2.47 
1.34 
1.03 
Calories. 
Calories. 
Calories. 
Per cent. 
4.99 
12.34 
11.89 
4.03 
3.25 
3.58 
13.60 
26.64 
12. 62 
1.99 
33. 00 
1.03 
4.64 
6.37 
12.59 
Per cent. 
11.80 
Per cent. 
4.43 
1638C 
1638E 
1639 
... .do .. 
11.48 
12.38 
16.05 
20.74 
8.88 
8.77 
7.48 
7.66 
2.40 
21.77 
19.69 
17.20 
4 40 
1660 
IllinoisNo.il 15 
Indiana No. 4 
Massachusetts peat . . 
North Dakota No.3 .. 
do 
2 62 
IS II 
2828 
2243 
2255 
1.32 
1.00 
1.57 
.CO 
.53 
.69 
.40 
.74 
.53 
2.56 
6, 426 
4. 055 
4,498 
6,265 
4,049 
4,431 
-11 
35 
3 
2.59 
.58 
1.32 
1.22 
2062 
Ohio No. 5 
7,501 
7,375 
-86 
1.76 
2718 
Texas No. 1 
1867 
2131 
2275 
West Virginia No 13. 
Wyoming No. 2 
Wyoming No. 2 15 
Wyoming No. 3 
8,408 
5, 815 
8.359 
5,747 
-17 
-26 
.83 
4.22 
4.09 
2278 
5,108 
4,903 
-75 
6.86 
The oxidation changes in every case are sufficiently large to be of 
practical importance, the smallest change — that in the Ohio No. 5 sam- 
ple — being 0.53 per cent, while the Illinois No. 9B sample showed a 
change of 2.47 per cent. The Wyoming No. 3 sample showed an 
increase of 2.56 per cent in weight and a decrease of 205 calories in 
heating value. The changes in weight correspond to a decrease in 
heating value of 144 calories, the final calorific value obtained being 
75 calories lower than is accounted for by the changes in weight. 
Further results along these lines are desirable, but the values already 
obtained show very clearty that old samples of coal can not be regarded 
as representative of the original coal in composition or in calorific 
value. 
