RESULTS OP SOFT-POEK INVESTIGATIONS, II 
15 
clearly illustrated. It is apparent that the hardening progressed 
much more slowly than the softening which preceded it. This seems 
true particularly of the group which made an average gain of 62 
pounds on peanuts. The curve for the group which made an average 
gain of 38 pounds on peanuts may be somewhat misleading, however, 
as it is based on data from a smaller number of animals than the 
other. It is probable that with a larger number of hogs the curve 
would more nearly parallel the other. Neither of the curves makes 
a close approach to the base curve which represents the increasing 
firmness of hogs grown and fattened exclusively on corn with non- 
softening supplements. At the nearest point there is a difference of 
5.5 points in refractive index. 
It is apparent in comparing these results with those obtained from 
pigs having initial weights of from 85 to 114 pounds, inclusive, that 
it is fully as difficult to produce firm hogs from the heavier pigs 
as from the lighter. In fact, there is an indication that the harden- 
ing progresses more slowly in the heavier pigs, the gains on peanuts 
having been equal. Obviously, the deduction must be made that 
it is as impracticable, or probably more so, under the ordinary 
economic conditions, to attempt to produce hard or medium-hard 
hogs from the heavier pigs as from 85 to 114 pound pigs, when this 
plan of feeding is used. These results strongly suggest that if a prac- 
tical plan of producing firm hogs under this system of feeding is to 
be developed it must make use of pigs weighing less than 85 pounds 
at the beginning of the peanut feeding. 
FEEDING RESULTS WITH CORN AND TANKAGE FOLLOWING PEANUTS 
Feeding results are available from one experiment in which corn 
was fed with tankage following peanuts to pigs having an average 
initial weight over 114 pounds. The pigs were fed at the Animal 
Husbandry Experiment Farm during the years 1924-25. 
The peanuts used in this experiment were low grade, shelled, or of 
the grade known commercially as " pickouts " or " shelling stock." 
The .composition is shown in Table 3. 
Table 3. — Composition of shelled peanuts 
Water 
Ash 
Crude 
protein 
Fiber 
Nitro- 
gen-free 
extract 
Fat 
Per cent 
4.9 
Per cent 
5.7 
Per cent 
26.3 
Per cent 
2.5 
Per cent 
24.3 
Per cent 
36.3 
The peanuts were self-fed, free choice, with mineral mixture 5 for 
56 days, when a hardening period of 24 weeks' duration was begun. 
Shelled corn, tankage, and mineral mixture, self-fed, free choice, 
were used for the hardening purposes. Killings of 10, 9, and 10 hogs 
were made after 16, 20, and 24 weeks' hardening, respectively, but in 
reporting results in Table 4 only a general average of data for all the 
5 Mineral mixture composed as follows: Charcoal, 75 pounds (3 bushels) ; raw phosphate 
rock, 3 pounds ; common salt, 6 pounds ; Glauber salt, 6 pounds ; ground limestone, 6 
pounds ; flowers of sulphur, 3 pounds; and copperas (pulverized sulphate of iron), 1 pound, 
71373°— 28 3 
