THEIR NATURE AND EFFECTS.
seconds longer. The whole time from injection to death was under 100 seconds.
Chart No. V. is a continuous tracing of the respiration of this animal from the administration of the poison till death. It will he seen that the normal respiratory rhythm is suddenly displaced hy violent alternate upheavings and depressions of the chest walls, and that then all movement at once stops. But it will he noticed that the convulsions, though, of course, irregular, have a distinctly respiratory character. When cobra-poison, then, enters the circulation in large quantity, it stimulates the respiratory centre to such a degree that convulsive action of the respiratory muscles is produced, but after a very brief period complete and permanent paralysis of "the respiratory apparatus is induced. It is worthy of note that rapid as death in this case was, the action of the heart continued after that of the respiration had ceased.
To sum up the different modes in which cobra-poison destroys the respiratory function : — First, almost instantaneous paralysis of the respiratory centre, a primary stimulation of a very violent but very transient character having occurred. This form of death must be exceedingly rare, if it ever occur, in the human subject, as the shortest period of fatal poisoning in man on record appears to have been a little under a quarter of an hour. Secondly, a more gradual method, the poison
