, and the glow of arterial blood, in the
cutaneous vessels; and lastly, the action of the stomach is much impaired
or destroyed, as appears by the total want of appetite to solid food.
Whence it would seem, that the torpid motions of the stomach, whatever may
occasion them, are a very frequent cause of continued fever with weak
pulse; and that these torpid motions of the stomach do not sufficiently
excite the sensorial power of association, which contributes in health to
actuate the heart and arteries along with the irritation produced by the
stimulus of the blood; and hence the actions of these organs are weaker.
And lastly, that the accumulation of the sensorial power of association,
which ought to be expended on the motions of the heart and arteries,
becomes now exerted on the cutaneous and pulmonary capillaries. See
Supplement I. 8. and Sect. XXXV. 1. 1. and XXXIII. 2. 10.

I have dwelt longer on the vertiginous diseases in this genus, both because
of their great intricacy, and because they seem to open a road to the
knowledge of fever, which consists of associated trains and tribes of
irritative or sensitive motions, which are sometimes mixed with the
vertiginous ones, and sometimes separate from them.

* * * * *

ORDO II.

_Decreased Associate Motions._

GENUS II.

_Catenated with Sensitive Motions._

In this genus the sensorial power of association is exerted with less
energy, and thence the actions produced by it are less than natural; and
pain is produced in consequence, according to the fifth law of animal
causation, Sect. IV. This pain is generally attended with coldness of the
affected part, and is seldom succeeded by inflammation of it. This
decreased action of the secondary link of the associated motions, belonging
to this genus, is owing to the previous exhaustion of sensorial power
either in the increased actions of the primary link of the associated
motions, or by the pain which attends them; both which are frequently the
consequence of the stimulus of something external to the affected fibres.

As pain is produced either by excess or defect of the natural exertions of
the fibres, it is not, considered separately, a criterion of the presence
of either. In the associations belonging to this genus the sensation of
pain or pleasure produces or attends the primary link of the associated
motions, and very often gives name to the disease.

When great pain exists withou