of the skin; as was formerly demonstrated by the late Dr. Munro,
(Edin. Medical Essays) and if in this patient the urine had been
re-absorbed into the mass of blood, as the bile in the jaundice, why was it
not detected in other parts of the body, as well as in the arm-pits?

6. Cathartic and vermifuge medicines applied externally to the abdomen,
seem to be taken up by the cutaneous branch of lymphatics, and poured on
the intestines by the retrograde motions of the lacteals, without having
passed the circulation.

For when the drastic purges are taken by the mouth, they excite the
lacteals of the intestines into retrograde motions, as appears from the
chyle, which is found coagulated among the faeces, as was shewn above,
(sect. 2 and 4.) And as the cutaneous lymphatics are joined with the
lacteals of the intestines, by frequent anastomoses; it would be more
extraordinary, when a strong purging drug, absorbed by the skin, is carried
to the anastomosing branches of the lacteals unchanged, if it should not
excite them into retrograde action as efficaciously, as if it was taken by
the mouth, and mixed with the food of the stomach.

VIII. _Circumstances by which the Fluids, that are effused by the
retrograde Motions of the absorbent Vessels, are distinguished._

1. We frequently observe an unusual quantity of mucus or other fluids in
some diseases, although the action of the glands, by which those fluids are
separated from the blood, is not unusually increased; but when the power of
absorption alone is diminished. Thus the catarrhal humour from the nostrils
of some, who ride in frosty weather; and the tears, which run down the
cheeks of those, who have an obstruction of the puncta lacrymalia; and the
ichor of those phagedenic ulcers, which are not attended with inflammation,
are all instances of this circumstance.

These fluids however are easily distinguished from others by their
abounding in ammoniacal or muriatic salts; whence they inflame the
circumjacent skin: thus in the catarrh the upper lip becomes red and
swelled from the acrimony of the mucus, and patients complain of the
saltness of its taste. The eyes and cheeks are red with the corrosive
tears, and the ichor of some herpetic eruptions erodes far and wide the
contiguous parts, and is pungently salt to the taste, as some patients have
informed me.

Whilst, on the contrary, those fluids, which are effused by the retrograde
action of the lymphatics, are for the