Although the wounds of venomous serpents are frequently attended with fatal results, such are not necessarily invariable. There are times and seasons when all reptiles are sluggish and inactive, and when they inflict comparatively trifling injuries; and the poison is much less virulent at certain periods than others--during chilling weather for instance, or when exhausted by repeated bites in securing sustenance. Young and small serpents, too, are less virile than large and more aged specimens, and it has likewise been observed that death is more apt to follow when the poison is received at the beginning or during the continuance of the heated term. The action of the venom is commonly so swift that its effects are manifested almost immediately after inoculation, being at once conveyed by the circulatory system to the great nervous centers of the body, resulting in rapid paralysis of such organs as are supplied with motive power from these sources; its physiological and toxicological realizations being more or less speedy accordingly as it is applied near or remote from these centers, or infused into the capillary or the venous circulation. Usually, too, an unfortunate experiences, perhaps instantaneously, an intense burning pain in the member lacerated, which is succeeded by vertigo, nausea, retching, fainting, coldness, and collapse; the part bitten swells, becomes discolored, or spotted over its surface with livid blotches, that may, ultimately, extend to the greater portion of the body, while the poison appears to effect a greater or less disorganization of the blood, not by coagulating its fibrine as Fontana surmised, but in dissolving, attenuating, and altering the form of its corpuscles, whose integrity is so essential to life, causing them to adhere to one another, and to the walls of the vessels by which they are conveyed; being no longer able to traverse the capillaries, oedema is produced, followed by the peculiar livid blush. Shakespeare would appear to have had intuitive perception of the nature of such subtle poison, when he caused the ghost to describe to Hamlet "The leprous distillment whose effect Bears such an enmity to the blood of man That swift as quicksilver, it courses through The natural gates and alleys of the body And with sudden vigor it doth posset And curd like eager droppings into milk, The thin and wholesome blood: so did it mine And a most instant tetter marked about Most lazar like, with vile and loathsome crust All my smooth body."