ANIMAL MECHANICS. 



67 



and, finally, 



r ^ 6io.c „ t 



K= = 1 10.4 lbs.* 



5-53 



The cross sections of the muscles were found, by cutting 

 them across with a sharp scalpel, and marking out their sec- 

 tion on cardboard, and afterwards weighing the marked por- 

 tions, the weights of which were then compared with the 

 weight of a known number of square inches of the same card- 

 board, and so the cross sections in square inches calculated. 



I give here, for the purpose of illustration, the actual sec- 

 tions of two of the muscles of the leg: — 



Fig. z. — Semitendino&us. 



Fig. 3. — Short Head of Biceps. 



* As it was not convenient to procure a good subject destroyed by a violent 

 death, I made use of a powerful man who had died of cholera, and who had been 

 a blacksmith by profession. Now, it is natural to suppose that the muscles of 

 the arm of a blacksmith are more developed than those of his leg, so that their 

 cross section would be relatively too great, and the coefficient derived from that 

 cross section, therefore, probably too small ; a circumstance which may help to 

 account for the smaller coefficient, 94. 7 lbs., found from the cross section of the 

 muscles flexing the forearm. 



It is well known that after death by cholera, life continues in the muscles, 

 and manifests itself for some hours by movements, and by the existence of the 

 muscular susurrus. Both of these facts I have repeatedly verified. It appeared 

 to me, therefore, that such a subject as I selected was one well suited to the pur- 

 pose of my observations. 



F 2 



