216 MANUAL OF CATTLlS-FEEDIlSiG. 



that made by Fick & Wislicenus,* in 1866. Tliese ob- 

 servers found that in the ascent of an Alpine peak (the 

 FauUiorn) the amount of protein decomposed, as measured 

 by the urea excreted, was not sufiicieiit, according to their 

 calculations, to jield the amount of force actually exerted 

 in raiohig their bodies to the height of the mountain, al- 

 though no allowance was made for the work of the internal 

 organs or for those muscular exertions which did not con- 

 tribute to the raising of their bodies, and though the heat 

 of combustion of protein was, in the absence of positive 

 data, assumed to be considerably higher than it was after- 

 ward found to be by Frankland. 



Here we have a perfectly definite amount of work per- 

 formed and the most favorable assumptions made on 

 doubtful points, and yet we have a considerable deficit of 

 foiTe, if the albuminoids alone are taken into account- 



At the time when Fick & Wislicenus made their experi- 

 ment no data as to the heat of combustion of the nutrients 

 were available; but shortly afterward Frankland f took 

 up the matter and made a large number of experiments 

 with the object of accurately determining these important 

 quantities. His results have served as the basis for several 

 calculations similar to those of Fick & Wislicenus, most, 

 if not all, of which have led to the same conclusion as did 

 theirs, viz., that the observed decomposition of protein 

 was insufficient to account for the amount of force actually 

 exerted. 



These results, if trustworthy, show that at least a por- 

 tion of the force exerted in muscular work must be con- 

 tributed by other ingredients of the food than protein. 



* PhU Mag., XXXT., 485. 

 •1 Ibid , XXXII , 182. 



