90 TRANSVERSELY STRIPED MUSCULAR FIBRES. 



dilute hydrochloric acid constitutes the essential part of the mus- 

 cular fibrils, and is perfectly identical with the substance of the 

 smooth muscular fibres of other contractile tissues. 



The ratio which the sarcolemma bears to the enclosed cylinder 

 of muscular fibre has never been even approximately determined. 

 The usual method of determining the connective tissue contained 

 in the muscles is by ascertaining the quantity of gelatin yielded by 

 boiling the previously rinsed muscle,, but this can only be regarded 

 as a very rough mode of determination. Liebig gives 5 '6$ as 

 the mean quantity of gelatigenous substance in flesh ; von Bibra 

 found about 2 in the majority of the different kinds of flesh 

 which he examined. 



If we take the gelatin that is formed as a measure of the quan- 

 tity of connective tissue contained in the muscles, we must bear 

 in mind that, on boiling with water, the nuclear fibres (which, it 

 would appear from micro-chemical investigations, are present in 

 considerable quantities in the muscles) remain undissolved, whilst 

 the protein- substance, in quantities varying according to the dura- 

 tion of the boiling, becomes dissolved with the gelatin (Mulder's 

 tritoxide of protein). 



Liebig estimates the constituents of ox-flesh which are soluble in 

 water at 6, of which 2*96 are albumen. This result agrees with 

 the analyses of Berzelius, Braconnot, Schiitz, Schlossberger, and 

 von Bibra. In the flesh of birds the quantity of soluble sub- 

 stances amounts to as much as 8-, as is shown by the analyses of 

 Schlossberger and von Bibra. 



Fat is always to be found in flesh, notwithstanding the most 

 careful preparation of the muscle, being derived not only from fat- 

 cells, but from the blood, the nerves, and even from the muscular 

 substance itself, in the fibrils of which we frequently observe fat- 

 globules amongst the nuclei. Liebig always found 2% in the flesh 

 of the ox, von Bibra found even as much as 4*24 J- in that of a 

 ,man aged fifty-nine years, but only about 2% in that of other mam- 

 mals, whilst he could not discover more than about from 0'54 to 

 1'11-J- in the muscle of fishes. 



The quantity of water in the muscles, when in a fresh state, 

 was estimated by Berzelius* at 77*l7feby Schlossbergerf at 77'5, 

 and by SchutzJ at 77'6, in the ox; von Bibra found from 72'56 



* Lehrb. de Chem. Bd. 9, S. 588. 

 t Untersuch. iiber d. Fleisch verschiedner Thiere. 



Vergleichende chem. Untersuchungen des Fleisches verschiedner Thiere. 

 1841. 



