CONTRACTILITY OF THE MUSCLES RIGOR MORTIS. 827 



more slowly thrown into contraction by mechanical stimuli than they are in 

 adults. The most remarkable manifestations of it yet observed, however, 

 have been witnessed after death from Cholera and Yellow Fever ; for in 

 these cases the muscular contractions, though capable of being excited by 

 mechanical stimulation applied to the muscles themselves, are frequently 

 spontaneous, and sometimes give rise to movements strongly resembling the 

 ordinary actions of the living state. In regard to the occurrence of this 

 phenomenon, after death from yellow fever, several interesting observations 

 have been recorded by Dr. Bennet Dowler, of New Orleans. 1 In one case, 

 the subject of which was an Irishman, aged twenty eight, the following 

 series of movements took place spontaneously not long after the cessation of 

 the respiration ; first the left hand was carried by a regular motion to the 

 throat, and then to the crown of the head ; the right arm followed the same 

 route on the right side; the left arm was then carried back to the throat, 

 and thence to the breast, reversing all its original motions, and finally the 

 right hand and arm did exactly the same. Similar phenomena have been 

 described by Mr. N. B. Ward, Mr. Helps, and Mr. Barlow,' 2 as occurring in 

 the bodies of cholera patients. Many circumstances indicate' that these 

 movements were due to the inherent contractility of the muscles, and were 

 not in any degree dependent upon the operation of the nervous system; and 

 Mr. Dowler proved experimentally, by completely separating limbs which 

 exhibited these movements from the trunk of the body, that the influence 

 of the nervous system was not in any degree essential to their production. 



677. The Rigor Mortis, or Cadaveric rigidity of the muscles, is essentially 

 the result of the coagulation of myosin (which, according to Michelsohn, is 

 due to the action of a ferment). 3 It begins immediately after all indications 

 of irritability have departed, but before any putrefactive change has com- 

 menced. The supervention of the rigidity is not usually prolonged much 

 beyond seven hours, though a tetanic state at first sight resembling it may 

 occasionally be observed to occur instantly after death from some peculiar 

 conditions of the nervous and muscular systems at the moment. In other 

 instances twenty or even thirty hours may elapse before it shows itself. Its 

 general duration is from twenty-four to thirty-six hours, but it may pass off 

 much more rapidly, or it may be prolonged to four or six days. It first 

 affects the neck and lower jaw, then the trunk, then the upper extremity, 

 and finally, the muscles of the lower extremities. In its departure, which is 

 immediately followed by decomposition, the same order is followed. It is 

 remarkable that it is equally intense in muscles which have been paralyzed 

 by Hemiplegia, or whose nerves have been previously severed, provided that 

 no considerable change has taken place in their nutrition. It was the opinion 

 of Mr. Hunter that death from exhaustion by hunting, as well as by light- 

 ning, completely prevents the post-mortem rigidity of muscles, and the coagu- 

 lation of the blood. But the observations of Gulliver 4 have proved that in 

 animals killed by hunting and by fighting, the rigor mortis is greatly has- 

 tened, and that the blood does coagulate. He found that deer, foxes, and 

 hares became quickly stiff after being hunted to death ; and that game fowls, 

 exhausted and worried to death by fighting, become quite stiff, and have the 

 blood coagulated in their hearts within twenty-eight minutes after the last 

 fatal wound. The immersion of Batrachian reptiles in water at a tempera- 

 ture of about 120 kills them instantly, when their muscles become imme- 



1 Experimental Researches on the Post-mortem Contractility of the Muscle*, 1845. 



2 See Mr. F. Barlow's Observations on the Muscular Contractions which occasion- 

 ally occur after Death from Cholera, in Mod. Gazette for 1849-50. 



3 ' Journ. of Anat. and Phys , 1874, p. 213. 

 4 Edinb. Med. and Surg. Journ., Oct. 1848. 



