STRIATED MUSCULAR FIBRE. 395 



had proved this to be the fact some years ago. We "have to con- 

 sider the composition of 



I. The muscular fluid. 

 II. The musculine. 

 III. The myolemma, containing both of the preceding. 



I. The "muscular juice," as it is termed by Liebig, surrounds the 

 fibre-cells of the smooth muscle ; and is also contained within the 

 myolemma of striated muscular fibre, where it permeates between 

 the fibrillas. It is easily expressed from fresh muscle, and is a de- 

 cidedly acid, albuminous fluid. Its albumen may, however, be in 

 part obtained from the blood of the muscular mass; while its large 

 amount of caseine is peculiar to it. 1 It is from 72.56 to 74.45 per 

 cent, water ( Von Bibra) ; there being, on an average, 10 per cent. 

 less water in muscle than in blood-serum. It also contains creatine, 

 creatinine, inosic acid, lactic acid, and a very little fat. Scherer has 

 also found in it acetic and formic acid ; and in that obtained from 

 the heart of the ox, he found a peculiar substance which he terms 

 inosite or muscle-sugar. The muscular juice, like most acid fluids, 

 also contains an abundance of potash salts, and of phosphates, while 

 it is poor in salts of soda and in chlorides. It appears that in the 

 horse there are twenty-nine times, and in the ox forty six times, as 

 much potash in the muscular juice as in the blood. There is about 

 ten times as much chloride of sodium, on the other hand, in the 

 blood-serum as in the muscular juice of the horse. (R. Weber.) 

 While the phosphate of lime is far more abundant in the blood 

 than the phosphate of magnesia, the reverse is true of the muscular 

 fluid. It has been seen that the chloride of potassium is more abun- 

 dant than that of sodium, and that the former is often mistaken for 

 the latter (p. 49). About twenty-three times as much phosphoric 

 acid exists in the ash of horse's muscle as in that of the blood- 

 serum; more than is sufficient to form all the neutral phosphates 

 of the alkalies. 



What the precise relation is between the function of the muscular 

 fibre on the one hand, and the chemical constitution of the muscu- 

 lar fluid on the other, is unknown. Liebig calculates that the stri- 

 ated muscles alone contain more than enough free acid to destroy 

 the alkalinity of all the blood ; and that the opposite state, in this 



1 The fluid of the smooth, however, contains more caseine and less albumen than 

 that of striated muscle. In the latter, albumen alone is often found. 



