314 NATURE AND LIFE. 
injection, the motions cease, and give place to the spasms 
of agony, and then to death. 
Physiologists asked whether such a momentary resur- 
rection of the functions of life might not be brought about — 
in the human subject—that is, whether movement might 
not be excited and expression reanimated by injecting fresh 
blood into a head just severed from a man’s body, as in 
"Brown-Séquard’s experiment. It was suggested to try it 
on the heads of decapitated criminals, but anatomical obser- 
vations, particularly those of Charles Robin, showed that 
the arteries of the neck are cut by the guillotine in such a 
way that air penetrates and fills them. It follows that it 
is impracticable to inject them with blood that can produce 
the effects noted by Brown-Séquard. Indeed, we know 
that blood circulating in the vessels becomes frothy on con- 
tact with air, and loses fitness for its functions. Robin 
supposes that the experiment in question could be success- 
ful only if made upon the head of a man killed by a ball 
that should strike below the neck; in that case it would be 
possible to effect such a section of the arteries that no en- 
trance of air would occur, and, if the head were separated 
at the place pointed out by Brown-Séquard, those mani- 
festations of function remarked in the dog’s head would 
probably be obtained by the injection of oxygenated blood. 
Brown-Séquard is convinced that they might be obtained, 
if certain precautions were observed, even with the head 
of a decapitated criminal; and so strong is his conviction 
that, when it was proposed to him to try the experiment— 
that is, to perform the injection of blood into the head of a 
person executed—he refused to do so, not choosing, as he 
said, to witness the tortures of this fragment of a being re- 
called for an instant to sensibility and life. We under- 
stand Brown-Séquard’s scruples, but it is allowable to 
doubt whether he would have inflicted great suffering on the 
head of the subject; at most, he would only have aroused in 
