EXAMPLES OF THE FOUR METHODS. 



Cthly. The series of instances which we shall take last, is 

 of a more complex character, and requires a more minute 

 analysis. 



It has long been observed that in some cases of death by 

 lightning, cadaveric rigidity either does not take place at all, 

 or is of such extremely brief duration as to escape notice, and 

 that in these cases putrefaction is very rapid. In other cases, 

 however, the usual cadaveric rigidity appears. There must be 

 some difference in the cause, to account for this difference in 

 the effect. Now " death by lightning may be the result of, 

 1st, a syncope by fright, or in consequence of a direct or reflex 

 influence of lightning on the par vagum ; 2ndly, hemorrhage 

 in or around the brain, or in the lungs, the pericardium, &c. ; 

 Srdly, concussion, or some other alteration in the brain ;" none 

 of which phenomena have any known property capable of 

 accounting for the suppression, or almost suppression, of the 

 cadaveric rigidity. But the cause of death may also be that 

 the lightning produces " a violent convulsion of every muscle 

 in the body," of which, if of sufficient intensity, the known 

 effect would be that " muscular irritability ceases almost at 

 once." If Dr. Brown-Sequard's generalization is a true law, 

 these will be the very cases in which rigidity is so much 

 abridged as to escape notice ; and the cases in which, on the 

 contrary, rigidity takes place as usual, will be those in which 

 the stroke of lightning operates in some of the other modes 

 which have been enumerated. How, then, is this brought tc 

 the test ? By experiments not on lightning, which cannot be 

 commanded at pleasure, but on the same natural agency in a 

 manageable form, that of artificial galvanism. Dr. Brown- 

 Sequard galvanized the entire bodies of animals immediately 

 after death. Galvanism cannot operate in any of the modes in 

 which the stroke of lightning may have operated, except the 

 single one of producing muscular convulsions. If, therefore, 

 after the bodies have been galvanized, the duration of rigidity 

 is much shortened and putrefaction much accelerated, it is 

 reasonable to ascribe the same effects when produced by light- 

 ning, to the property which galvanism shares with lightning, 

 and not to those which it does not. Now this Dr. Brown- 



