id,
belong to this genus; as the gout, rheumatism, erysipelas. It is probable
many other inflammations may, by future observation, require to be
transplanted into this class.

The circles of sensitive associate motions consist chiefly of the excretory
ducts of the capillaries and of the mouths of the absorbent vessels, which
constitute the membranes; and which have been induced into action at the
same time; or they consist of the terminations of canals; or of parts which
are endued with greater sensibility than those which form the first link of
the association. An instance of the first of those is the sympathy between
the membranes of the alveolar processes of the jaws, and the membranes
above or beneath the muscles about the temples in hemicrania. An instance
of the second is in the sympathy between the excretory duct of the lacrymal
gland, and the nasal duct of the lacrymal sack. And an instance of the
third is the sympathy between the membranes of the liver, and the skin of
the face in the gutta rosea of inebriates.

SPECIES.

1. _Lacrymarum fluxus sympatheticus._ A flow of tears from grief or joy.
When the termination of the duct of the lacrymal sac in the nostrils
becomes affected either by painful or pleasurable sensations, in
consequence of external stimulus, or by its association with agreeable or
disagreeable ideas, the motions of the lacrymal gland are at the same time
exerted with greater energy, and a profusion of tears succeeds by sensitive
association, as explained in Sect. XVI. 8. 2.

In this case there exists a chain of associated actions, the secretion of
the lacrymal gland is increased by whatever stimulates the surface of the
eye, at the same time the increased abundance of tears stimulates the
puncta lacrymalia into greater action; and the fluid thus absorbed
stimulates the lacrymal sac, and its nasal duct in the nose into greater
action. In a contrary direction of this chain of association the present
increase of action is induced. First, the nasal duct of the lacrymal sac is
excited into increased action by some pleasurable or painful idea, as
described in Sect. XVI. 8. 2. 2d. The puncta lacrymalia or other
extremity of the lacrymal sac sympathizes with it (as the two ends of all
other canals sympathize with each other). 3d. With these increased
motions of the puncta lacrymalia those of the excretory duct of the
lacrymal gland are associated from their having so perpetually acted
together.