aughter; as described in Sect.
XXXIV. 1. 4. The tickling of the nostrils, which precedes the efforts of
sneezing, is owing to the increased irritation occasioned by external
stimulus; and is attended with a pleasureable sensation in consequence of
the increased action of the part. When this action is exerted in a greater
degree, the sensation becomes painful, and the convulsion of sneezing
ensues; as the pain in tickling the soles of the feet of children is
relieved by laughter.

A lady after a bruise on her nose by a fall was affected with incessant
sneezing, and relieved by snuffing starch up her nostrils. Perpetual
sneezings in the measles, and in catarrhs from cold, are owing to the
stimulus of the saline part of the mucous effusion on the membrane of the
nostrils. See Class II. 1. 1. 3.

9. _Pruritus._ Itching seems to be a greater degree of titillation, and to
be owing to the stimulus of some acrid material, as the matter of the itch;
or of the herpes on the scrotum, and about the anus; or from those
universal eruptions, which attend some elderly people, who have drank much
vinous spirit. It occurs also, when inflammations are declining, as in the
healing of blisters, or in the cure of ophthalmia, as the action of the
vessels is yet so great as to produce sensation; which, like the
titillations that occasion laughter, is perpetually changing from pleasure
to pain.

When the natural efforts of scratching do not relieve the pain of itching,
it sometimes increases so as to induce convulsions and madness. As in the
furor uterinus, and satyriasis, and in the sphincter ani and scrotum. See
Class II. 1. 4. 14. IV. 2. 2. 6.

M. M. Warm bath. Fomentation. Alcohol externally. Poultice. Oiled silk.
Mercurial ointments on small surfaces at once. See Class II. 1. 4. 12.
Solutions of lead on small surfaces at once.

10. _Dolor urens._ Smarting follows the edge of a knife in making a wound,
and seems to be owing to the distention of a part of a fibre, till it
breaks. A smarting of the skin is liable to affect the scars left by herpes
or shingles; and the callous parts of the bottoms of the feet; and around
the bases of corns on the toes; and frequently extends after sciatica along
the outside of the thigh, and of the leg, and part of the foot. All these
may be owing to the stimulus of extension, by blood or serum being forced
into vessels nearly coalesced.

M. M. Emplastrum de minio put like a bandage on the part. Warm fom