104 PRESERVATION OF FOOD BY REFRIGERATION ; 
sr 
Thickness in inches... 2 g 4 5 6 
Average temperature... 89° 84° 81° Fer ese 
Fall from 98°... os) O° 014° G7 ity eens 
Heat lost in units --. 26.» 82,148 “234 igzaeiaieg 
The average rate of the emission being found, and the 
number of units of heat to be removed being also shown, 
the time required is obtained. 
(F) 
Thickness in inches I 2 g 4 5 6 
Time in hours ... o'2 of8° 1°6 “2'GIGg Veeeee 
2nD.—THE REDUCTION OF THE INTERNAL SURFACE TO 32°. 
The total number of units of heat to be abstracted from 
meat of various thicknesses in bringing the temperature 
down to 32° being shown in table 8, and also the loss 
during the first part of the process having been ascertained 
(E), the remainder is that to be abstracted during the 
second part of the operation. This is now given :— 
(G) 
Thickness in inches I 2 3 4 5 6 
Units to be removed 169 304 431 539 645 756 
The flow of heat at the end of the first part of the process 
being given in (c), and also the emission, when the internal 
surface temperature has fallen to 32° (table g), varying 
with the temperature of the air and the different thick- 
nesses, the average rate of the flow for the second part is 
thus obtained :— 
(A) 
Thickness in inches ... I 2 3 4 5 6 
Flow at commencement 
in units ... eS 95 74 61 52 45 go 
surface is at 32°. 
From table 10 
Average flow ... we $7°5 37 315 27c5.eedi gees 
Knowing the average rate of emission (H) and the total 
number of units to be removed (G), the time required is 
thus obtained. 
Flow when the internal 
fe) fe) 2 2 4 5 
