_
| R' - R |
C = N|R + ------ (T" - T)| (19)
|_ T' - T _|

Where C = correction in degree centigrade,
N = number of intervals over which correction is made,
R = initial radiation in degrees per interval,
R' = final radiation in degrees per interval,
T = average temperature for period through which initial radiation
is computed,
T" = average temperature over period of combustion[39],
T' = average temperature over period through which final radiation
is computed.[39]

The application of this formula to Fig. 25 is as follows:

As already stated, the temperature at the beginning of combustion is the
reading just before the current is turned on, or B in Fig. 25. The point
C or the temperature at which combustion is presumably completed, should
be taken at a point which falls well within the established final rate
of radiation, and not at the maximum temperature that the thermometer
indicates in the test, unless it lies on the straight line determining
the final radiation. This is due to the fact that in certain instances
local conditions will cause the thermometer to read higher than it
should during the time that the bomb is transmitting heat to the water
rapidly, and at other times the maximum temperature might be lower than
that which would be indicated were readings to be taken at intervals of
less than one-half minute, _i. e._, the point of maximum temperature
will fall below the line determined by the final rate of radiation. With
this understanding AB, Fig. 25, represents the time of initial
radiation, BC the time of combustion, and CD the time of final
radiation. Therefore to apply Pfaundler's correction, formula (19), to
the data as represented by Fig. 25.

N = 6, R = 0, R' = .01, T = 20.29, T' = 22.83,

20.29 + 22.54 + 22.84 + 22.88 + 22.87 + 22.86
T" = --------------------------------------------- = 22.36
6

_ _
| .01 - 0 |
C = 6|0 + -------------(22.36 - 20.29)|
|_ 22.85 - 20.29 _|

= 6 x .008 = .048

Pfaundler's formula while simple is rather long. Mr. E. H. Peabody has
devised a simpler formula with which, under proper conditions, the
variation from correction as found by Pfaundler's method is negligible.

It was noted throughout an extended series of calorimeter tests t