Page:AJWall Indian Snake Poisons.djvu/47

32 natural to conclude that the principle action of cobra-poison on the nervous system consists of an extinction of function, extending from below upwards, of the various nerve centres constituting the cerebro-spinal system; and though, no doubt, other parts of the nervous system suffer, it is evident that cobra-poison has a special affinity for acting on the respiratory centre, and those other ganglia allied to it in the medulla oblongata, which are in connection with the vagus, the spinal accessory and the hypo-glossal nerves, and that it is directly to this destructive action that we have to attribute death in most cases of cobra-poisoning.

In very rapid cases of poisoning, when a very large quantity of poison has entered the circulation at once, instead of the gradual extinction of function of the cerebro-spinal centres, the poison appears to act almost immediately by stopping the action of the respiratory centre. There is, of course, no time in these cases to watch the gradual extension of the influence of the poison on the nervous system. It also happens that before cobra-poisoning paralyses the cerebro-spinal centres, it first stimulates them, and produces irregular action. This is sometimes very marked in regard to the respiratory centre, when a large quantity of cobra-poison has entered the circulation with considerable rapidity; and in this case it is very often se6n that the other centres in the cord have shared in this stimulation before becoming paralysed; the result being irregular