r
the following heads.

A. Associate motions distinguished from catenations.
B. Associate motions of three kinds.
C. Associations affected by external influences.
D. Associations affected by other sensorial motions.
E. Associations catenated with sensation.
F. Direct and reverse sympathy.
G. Associations affected four ways.
H. Origin of associations.
I. Of the action of vomiting.
K. Tertian associations.

A. _Associate Motions distinguished from Catenations._

Associate motions properly mean only those, which are caused by the
sensorial power of association. Whence it appears, that those fibrous
motions, which constitute the introductory link of an associate train of
motions, are excluded from this definition, as not being themselves caused
by the sensorial power of association, but by irritation, or sensation, or
volition. I shall give for example the flushing of the face after dinner;
the capillary vessels of the face increase their actions in consequence of
their catenation, not their association, with those of the stomach; which
latter are caused to act with greater energy by the irritation excited by
the stimulus of food. These capillaries of the face are associated with
each other reciprocally, as being all of them excited by the sensorial
power of association; but they are only catenated with those of the
stomach, which are not in this case associate motions but irritative ones.
The common use of the word association for almost every kind of connection
has rendered this subject difficult; from which inaccuracy I fear some
parts of this work are not exempt.

B. _Associate Motions of three Kinds._

Those trains or tribes of associate motions, whose introductory link
consists of an irritative motion, are termed irritative associations; as
when the muscles of the eyelids close the eye in common nictitation. Those,
whose introductory link consists of a sensitive motion, are termed
sensitive associations; as when the pectoral and intercostal muscles act in
sneezing. And lastly, those, whose introductory link consists of a
voluntary motion, are termed voluntary associations; as when the muscles of
the lower limbs act in concert with those of the arm in fencing.

C. _Associations affected by external Influences._

Circles of associate motions, as well as trains and tribes of them, are
liable to be affected by external influences, which consist of etherial
fluids, and which, by penetrating t