F. Action on Sensory Centres and the Reflexes.
The sensory sphere remains comparatively unaffected in mild cases, and in the early stages of more serious ones, but when paresis has deepened into paralysis, sensation becomes ever more blunted, and with the advent of coma, of course, quite extinct. Reflexes, both superficial and deep ones, are also completely abolished at this period of the poisoning process, and the nerves of special sense do not react against any, even the strongest possible stimulation. The eye stares vacantly into a glaring light held close before it, and the widely dilated pupil shows no sign of reaction. The ear also appears deaf to any noise, and strong ammonia vapour is inhaled through the nose like the purest air, whilst pricking, beating, and even burning the skin elicit not a quiver of a muscle.
Feoktistow's experiments with regard to reflexes, more especially their restoration by strychnine, differ in their results entirely from Australian observations. Whilst we have no difficulty in restoring them with the drug on man as well as the domestic animals, his experiments on frogs were a failure, and merely showed a decided antagonism between the two poisons. He did not succeed in restoring the reflexes, and, instead of following up with experiments on the higher animals, he trusted implicitly to his results on frogs, and thus lost his opportunity.