FORMATION OF FAT. 443 



which had been thus fed was very rich in fat, but poor in albumi- 

 nates ; the quantity of the muscular substance diminished per- 

 ceptibly, and where the fattening had been rapid the geese 

 exhibited an absolute loss of bodily weight. 



We do not here enter more fully into the individual series of 

 experiments which have been instituted on animals in connexion 

 with the process of feeding stock or of augmenting the quantity of 

 milk ; they were for the most part instituted solely in reference to 

 what was formerly regarded as a very doubtful question (see 

 pp. 211-216), whether food deficient in fat sufficed for the feeding or 

 fattening of animals, and whether fat could be produced in the 

 animal organism from the amylacea. They are consequently only 

 of interest to us in relation to the latter point. Although Liebig 

 at an early period demonstrated, partly by exact experiments, and 

 partly by the most ingenious application of various facts which 

 bore upon the point, that fat is formed in the animal body from 

 carbo-hydrates, this proposition was yet for a long time denied by 

 Dumas and Boussingault, and numerous experiments were made, 

 some of which appeared to favour and others to oppose Liebig's 

 view. As, however, we have already discussed this subject some- 

 what in detail (in vol. L, p. 254), we need here only mention two 

 series of experiments, by which the correctness of Liebig' s opinion 

 was placed beyond all further question. Dumas,* in conjunction 

 with Milne Edwards, repeated Gundelach's experiment of feeding 

 bees with honey freed from wax (at all events the honey em- 

 ployed as their food only contained one-ten-thousandth part of 

 wax). Of four swarrns which were employed in the experiment, 

 only a single one began to secrete wax and to build with it. The 

 numerical results of this investigation may be most easily seen in 

 the following manner : 



Fat which was found in the body of each bee at the be- 

 ginning of the experiment .... .... .... - G018 of agramme. 



Wax which, on an average, each bee consumed with the 

 honey during the whole of the experiment, did not 

 exceed .... .... .... .... .... 0-0003 



The whole amount of fatty matter whose origin might 

 possibly be derived from the food, averaged for each 

 bee at most .... .... .... .... 0'0022 



During the whole length of the experiment the wax 



secreted by each bee averaged .... .... .... 0064 ., 



At the termination of the experiment the wax or ordinary 



fat in the body of each bee averaged .... .... 0*0042 



* Journ. de Pliarm. et de Chim. 3 SeV. T. 9, p. 339-344. 



