ach, because vinous spirit excites the fibres of the
stomach into more violent action than the stimulus of common food; and the
cutaneous capillaries of the face, from their more frequent exposure to the
vicissitudes of cold and heat, possess more mobility or irritability than
those of other parts of the skin, as further explained in Sect. XXXIII. 2.
10. Vinegar is liable to produce this flushing of the face, which probably
is owing to the quantity of vinous spirit it contains, as I believe the
unfermented vegetable acids do not produce this effect. In every kind of
blush the arterial blood is propelled into the capillaries faster than the
venous absorption can carry it forwards into the veins, in this respect
resembling the tensio phalli.

Can the beginning vinous or acetous fermentation of the aliment in weak
stomachs contribute to this effect? or is it to be ascribed to the greater
power of association between the arteries of the face and the fibres of the
stomach in some people than in others?

M. M. Eat and drink less at a time, and more frequently. Put 20 drops of
weak acid of vitriol into water to be drank at meals. Let the dress over
the stomach and bowels be loose. Use no fermented liquors, or vinegar, or
spice.

2. _Sudor stragulis immersorum._ Sweat from being covered in bed. In the
commencement of an epidemic fever, in which the perpetual efforts to vomit
was a distressing symptom, Dr. Sydenham discovered, that if the patient's
head was for a short time covered over with the bed clothes, warmth was
produced, and a sweat broke out upon the skin, and the tendency to vomit
ceased. In this curious fact two trains of associated motions are excited
into increased action. First, the vessels of the lungs are known to have
their motion associated with those of the skin by the difficulty of
breathing on going into the cold bath, as described in Sect. XXXII. 3. 2.
Hence, when the vessels of the lungs become excited into stronger action,
by the bad air under the bed clothes, warmed and adulterated by frequent
breathing, those of the external skin soon become excited by their
association into more energetic action, and generate more heat along with a
greater secretion of perspirable matter. Secondly, the sympathy between the
stomach and skin is evident in variety of circumstances; thus the cold air
of frosty days applied to the skin for a short time increases the action of
the stomach by reverse sympathy, but decreases