OF THE MUSCULAR SYSTEM IN GENERAL. 431 



cular irritability continues longest after death. This duration 

 varies from one hour to twenty-four hours, or thereabout. 



690. Finally, after all irritability, general or local, has 

 ceased in the body deprived of life, cadaverous stiffness en- 

 sues.(124) It is an invariable phenomenon, whatever may 

 have been said of it by Haller and Bichat, but it varies in its 

 intensity as well as duration. This contraction or stiffness, 

 has its seat in the muscular system, and is independent of the 

 nervous system; it takes place only when this system has 

 ceased to possess any galvanic irritability. The section of the 

 nerves, the state of hemiplegia and the oblation of the nervous 

 centre, do not hinder it from manifesting itself. It is the last 

 effort of muscular contractility. In cold blooded animals, in 

 which nervous excitability continues fora long time, cadaver- 

 ous stiffness occurs late and continues but a short time, where- 

 as, in warm-blooded animals, it takes place soon after death 

 and continues a long time; in which nervous excitability is of 

 short duration. Cadaverous stiffness seems to be analogous to 

 the contraction of the fibrinous coagulum of the blood, and 

 like this, only ceases when putrefaction commences. It may 

 be considered, when joined to the coldness that always ac- 

 companies it, as a certain sign of death. If a muscle in a 

 state of stiffness be immersed and preserved in alcohol, that 

 stiffness will continue for an indefinite period. 



693. Other moving properties have been attributed to the 

 muscles. Galen recognised in them a tonic force, indepen- 

 dent of life; elasticity has likewise been ascribed to them; Hal- 

 ler ascribed to them contractile force in general, as well as 

 dead force; Sympson and Whytt attributed tonicity or tonic 

 force to them; Bichat, in addition to voluntary contractility, 

 and irritability or voluntary contractility, attributed to them 

 insensible organic contractility, that is to say tonicity. 



The muscles are extensible, they are retractile 'also, and this 

 independently of their contraction by irritation. In the state 

 of sleep and of repose the muscles furnish generally to the dif- 

 ferent parts of the body, mean attitudes depending on their 

 proportionate length, and consequently on their tension, on 

 their force, and on the manner, more or less efficacious, in 

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