action, and thence quickly exhaust the ill-supplied vascular muscles; for to rest is death; and therefore those vascular muscles continue to proceed, though with feebler action, to the extreme of weariness or faintness:  while nothing similar to this affects the locomotive muscles, whose actions are generally caused by volition, and not much subject either to irritation or to other kinds of associations besides the voluntary ones, except indeed when they are excited by the lash of slavery.

In these vascular muscles, which are subject to perpetual action, and thence liable to great accumulation of sensorial power during their quiescence from want of stimulus, a great increase of activity occurs, either from the renewal of their accustomed stimulus, or even from much less quantities of stimulus than usual.  This increase of action constitutes the hot fit of fever, which is attended with various increased secretions, with great concomitant heat, and general uneasiness.  The uneasiness attending this hot paroxysm of fever, or fit of exertion, is very different from that, which attends the previous cold fit, or fit of quiescence, and is frequently the cause of inflammation, as in pleurisy, which is treated of in the next section.

A similar effect occurs after the quiescence of our organs of sense; those which are not subject to perpetual action, as the taste and smell, are less liable to an exuberant accumulation of sensorial power after their having for a time been inactive; but the eye, which is in perpetual action during the day, becomes dazzled, and liable to inflammation after a temporary quiescence.

Where the previous quiescence has been owing to a defect of sensorial power, and not to a defect of stimulus, as in the irritative fever with weak pulse, a similar increase of activity of the arterial system succeeds, either from the usual stimulus of the blood, or from a stimulus less than usual; but as there is in general in these cases of fever with weak pulse a deficiency of the quantity of the blood, the pulse in the hot fit is weaker than in health, though it is stronger than in the cold fit, as explained in No. 2. of this section.  But at the same time in those fevers, where the defect of irritation is owing to the defect of the quantity of sensorial power, as well as to the defect of stimulus, another circumstance occurs; which consists in the partial distribution of it, as appears in partial flushings, as of the face or bosom, while the extremities are cold; and in the increase of particular secretions, as of bile, saliva, insensible perspiration, with great heat of the skin, or with partial sweats, or diarrhoea.

There are also many uneasy sensations attending these increased actions, which, like those belonging to the hot fit of fever with strong pulse, are frequently followed by inflammation, as in scarlet fever; which inflammation is nevertheless accompanied with a pulse weaker, though quicker, than the pulse during the remission or intermission of the paroxysms, though stronger than that of the previous cold fit.