THEIR NATURE AND EFFECTS.
contractions in various groups of muscles. They, however, are not so well marked as those produced by stimulation of the respiratory centre, but they are equally rapidly followed by complete paralysis.
Action of Cobra-Poison on the Respiration.
The action of cobra-poison on the respiratory function deserves the closest attention, as death is generally the direct result of the extinction of this function by the effect of the poison.
The first change that is noticed in the breathing of an animal after the introduction of cobra-poison, is a decided quickening and deepening of the respiratory movement. This effect is no longer to be perceived after section of the vagi, and it has been asserted that the acceleration is due to the stimulation of those nerves by the poison. But section of the vagi is always followed by excessive slowing of the respiratory movement; thus, in dogs, the respirations are generally reduced by one-half. It is not improbable, therefore, that an agent that would somewhat stimulate and accelerate the action of the respiratory centre, would fail in producing this result if administered directly after an operation that had so powerfully retarding effect. The inhibitory effect of section of the vagi may
be too great to allow of the accelerating action of the poison being perceived. But this quickening, however
