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12 the human subject, an interval of an hour occurs before any constitutional symptoms are developed. Under certain exceptional circumstances the symptoms of poisoning may begin almost at once. In the case of dogs bitten by cobras this interval varies very greatly — perhaps fifteen minutes may be taken as its average length, or perhaps a little less.

The retardation of the constitutional symptoms probably means that before cobra-poison can produce any, effect, it must be present in the blood in certain proportion, and, of course, in slow absorption, either due to the small quantity of the poison injected, or to its being injected into an unfavourable situation, some time must elapse before this proportion can be attained. In these cases the symptoms are delayed, as is also the fatal result ; whereas, should the poison enter the circulation rapidly, as by injection into a vein, the symptoms and fatal result follow immediately. At the same time it is clear that for a short time a fatal quantity of poison may be present in the circulation without producing a symptom ; for the bitten part may be sometimes amputated before the occurrence of any sign of poisoning, yet, nevertheless, the animal may die.

In man the first constitutional symptom that cobra poison produces seems to be a feeling of intoxication, although there appears to be no outward evidence of it. That this symptom is not more frequently described