owed 17.9 per cent to be combustible matter,
all of which is assumed to be carbon. The test showed 10.00 of the total
dry fuel fired to be ash. Hence 10.00x.179 = 1.79 per cent of the total
fuel represents the proportion of this total unconsumed in the ash and
the loss due to this cause is

1.79 per cent x 14,600 = 261 B. t. u.,
= 1.83 per cent.

The heat absorbed by the boilers per pound of dry fuel is 11.71x970.4 =
11,363 B. t. u. This quantity plus losses (A), (B), (C), (D) and (E), or
11,363+22+618+1311+61+261 = 13,636 B. t. u. accounted for. The heat
value of the coal, 14,225 B. t. u., less 13,636 B. t. u., leaves 589
B. t. u., unaccounted for losses, or 4.15 per cent.

The heat balance should be arranged in the form indicated by Table 58.

TABLE 58

HEAT BALANCE

B. T. U. PER POUND DRY COAL 14,225

+----------------------------------------------------------------------+
|+--------------------------------------------------------------------+|
|| |B. t. u.|Per Cent||
|+--------------------------------------------------+--------+--------+|
||Heat absorbed by Boiler | 11,363 | 79.88 ||
||Loss due to Evaporation of Moisture in Fuel | 22 | 0.15 ||
||Loss due to Moisture formed by Burning of Hydrogen| 618 | 4.34 ||
||Loss due to Heat carried away in Dry Chimney Gases| 1311 | 9.22 ||
||Loss due to Incomplete Combustion of Carbon | 61 | 0.43 ||
||Loss due to Unconsumed Carbon in the Ash | 261 | 1.83 ||
||Loss due to Radiation and Unaccounted Losses | 589 | 4.15 ||
|+--------------------------------------------------+--------+--------+|
||Total | 14,225 | 100.00 ||
|+--------------------------------------------------+--------+--------+|
+----------------------------------------------------------------------+

Application of Heat Balance--A heat balance should be made in connection
with any boiler trial on which sufficient data for its computation has
been obtained. This is particularly true where the boiler performance
has been considered unsatisfactory. The distribution of the heat is thus
determined and any extraordinary loss may be detected. Where accurate
data for computing such a heat balance is not available, such a
calculation based