304 THE ROTHAMSTED EXPERIMENTS. 



Percentages parts of fat, for 100 total fat in increase 33.2, and for 100 

 %rbofw-° m new ly _ f° rme d fat 49.7 parts, must have been derived from 

 drates. carbohydrates. 



Reckoning, as in the second column, that 90 per cent of the 

 nitrogenous substance and fatty matter consumed were digest- 

 ible and available, the calculations show that — for 100 increase 

 in live- weight 31.7 parts of fat, for 100 total fat in increase 

 40.1 parts, and for 100 newly-formed fat 57.3 parts, would be 

 derived from carbohydrates. Or, reckoning as in the third 

 column, that only 80 per cent of the nitrogenous substance 

 and fat of the food were digested and available, the results 

 show that — for 100 increase in live-weight 37.3 parts of fat, 

 for 100 total fat in the increase 47.2 parts, and for 100 newly- 

 formed fat 64.3 parts, or nearly two-thirds, of the total pro- 

 duced fat, would have its source in the carbohydrates. 



It may be observed that, in the case of this experiment with 



maize, the results given in the third column would very nearly 



accord with those which would be obtained if Wolff's average 



percentages of digestible had been adopted. 



Results Let us now refer to the results of experiment 5, in which 



able album- ^ ne ^ 00{ ^ was barley-meal alone, given ad libitum, and the 



inoid ratio, albuminoid ratio was nearly that recognised as most suitable 



for the rapid fattening of the pig. 



The first of the three columns, calculated on the assumption 

 that the whole of the nitrogenous substance and fat consumed 

 were digested, shows that under such conditions there would 

 be — for 100 increase in live-weight 30.3 parts of fat, for 100 

 total fat in increase 41.9 parts, and for 100 newly-formed fat 

 50.6 parts, or about half, that must have been derived from 

 other constituents than the fatty matter and nitrogenous sub- 

 stance of the food. 



The results in the second column, calculated on the as- 

 sumption that 90 per cent of the fatty matter and nitro- 

 genous substance were digested, show that — in 100 increase 

 in live-weight 34.8 parts of fat, in 100 of total fat in increase 

 48.1 parts, and of 100 newly-formed fat- 57.0 parts, must have 

 been formed from carbohydrates. 



Lastly, the results in the third column, reckoning only 80 



per cent of the nitrogenous substance and fat to be digested, 



show that on this supposition — of 100 increase in live-weight 



39.4 parts of fat, of 100 total fat in increase 54.5 parts, or of 



100 newly-formed fat 63.1, or again nearly two-thirds, must 



have been derived from carbohydrates. 



Evidence So much for the evidence of results relating to pigs, in their 



a^Tdtcis- Deai i n g on the question of the sources of their fat, when fed 



ive. on their appropriate fattening food. It is cumulative and 



decisive that, at any rate, a large proportion of the stored-up 



