1873.] 



Irritability after Systemic Death. 



347 



crying o£ the living child, it recovered sufficient power to breathe and even 

 to cry, and manifested evidence of life in all its muscles, except the 

 heart, for twenty minutes, when it had a severe convulsion, which stopped 

 all further motion. 



In this instance the author believed that the retention of muscular irri- 

 tability had depended upon the retention in the nervous organism of the 

 conditions necessary for exciting motion. He proceeded to describe his 

 researches as to the possibility of suspending nervous changes incident to 

 death, so as to retain the conditions requisite for the communication of 

 nervous impulse to muscular fibre. 



SUMilAET. 



1. There are three degrees of muscular irritability — the active efficient, 

 passive efficient, negative inefficient. The muscle after death may be 

 suspended in any of these conditions for action ; but, as a rule, it is the 

 last condition only that is maintained long after death. 



2. Muscular irritability may be suspended or stopped altogether under 

 three different conditions, having reference to its connexion with nervous 

 activity : — (a) The nervous and muscular activities may be suspended 

 equally, on which there may follow spontaneous return of motion. (5) 

 The muscular irritability may outlive the nervous function, on which the 

 phenomenon of irritability may be induced by the application of the 

 motor forces, but there is no return of spontaneous irritability, i. e. of 

 irritability belonging to the animal as an independent agent, (c) The 

 nervous function may outlive the muscular irritability, under which cir- 

 cumstances irritability is invariably stopped by the production of per- 

 sistent contractility of the muscular fibre. 



3. Nervous activity exciting muscular action is identical with all the 

 motor forces, and particular to none. It is equivalent to mechanical, 

 calorific, or electrical force, and equally susceptible of manifestation 

 through either. 



4. Muscular irritability after death is possible under conditions which, 

 so far, are thus known. Cold, in certain defined degrees, suspends 

 without destroying it. The motor forces strike it into rest. Blood 

 sustains it or stops it according to the balance of power existing between 

 the muscular and nervous systems. Some chemical agents suspend it 

 independently, others suspend it, together and equally, with suspension 

 of the nervous function. When suspension is equal there may be 

 spontaneous return ; when it is unequal there is no return. 



In conclusion, the author said there had been six great advances 

 in physiological medicine — viz. the introduction of the art of anatomy, 

 the discovery of the circulation of the blood, the discovery of the chemical 

 process of respiration and nutrition, the discovery of the ultimate struc- 

 ture of animal bodies, the discovery of osmosis and of the crystal- 



