by boilrng the -flesh for about half an hour, the reverse of this 

 occurred in some of the other cases ; for example, in the mus- 

 sel) the flesh of the ox and calf. These are mere observations 

 of facts, arising probably from accidental causes; the modifi- 

 cation which meat undergoes by boiling not being sufficiently 

 understood by chemists at pi-iesent, although Mulder has 

 proved the formation of oxide of proteine by it; from 

 the observations just made, no general conclusion can be 

 drawn, because they do not seem to coincide, at least at first 

 sight. 



* XXVIII. 0'271 grm. of the purified muscle of the had- 

 dock gave 0*671 grm. of ammonio-chloride of platinum, equal 

 to 15*72 per cent, of nitrogen. 



'• XXIX. 0-348 grm. of the flesh of the flounder, Platessa 

 FlessuSi gave 0*783 grm. of ammonio-chloride of platinum, 

 equal to 14*28 per cent, of nitrogen. 



'^^XXX. 0*342 grm. of boiled flounder gave 0*818 grm. of 

 ainmonio-chloride of platinum, equal to 15'18 per cent, of ni- 

 trogen. 



XXXI. 0*301 grm. of purified muscle of the flounder gave 

 0*745 grm. of ammonio-chloride of platinum, equal to 15*71 

 per cent, of nitrogen. 



We have selected the skate, Raia Batis, as a fair example 

 of the cartilaginous order of fishes. 



XXXII. 0*415 grm. of the flesh of the skate gave 1*066 

 grm. of ammonio-chloride of platinum, equal to 15*39 per 

 cent, of nitrogen. 



XXXIII. 0*402 grm. of boiled skate gave 0*964 grm. of 

 ammonio-chloride of platinum^ equal to 15*22 per cent, of ni- 

 trogen. 



XXXIV. 0*407 grm. of the boiled muscle taken from the 

 claw of the crabfish gave 0*877 grm. of ammonio-chloride of 

 platinum, equal to 13*66 per cent, of nitrogen. From this 

 analysis we are led to believe that the muscles of the Crustacea 

 are as rich in nitrogen as those of much more highly organised 

 animals. 



XXXV. 0*299 grm. of the flesh of the pigeon gave 0*570 

 grm. of ammonio-chloride of platinum, equal to 12*10 per 

 cent, of nitrogen. This is a surprisingly low number, more 

 especially as the muscle of this bird was nearly free of fat. 



■ XXXVI. 0*334 grm. of boiled pigeon gave 0*649 grm. of 

 ammonio-chloride of platinum, equal to 12*33 per cent, of ni- 

 trogen. 



XXXVII. 0*166 grm. of the purified muscle of the pigeon 

 gave 0*344 grm. of ammonio-chloride of platinum, equal to 

 13*15 per cent, of nitrogen. The fibre used in this experi- 



