prevent nausea, to allay vomiting, to palliate the foul odor of the
ship and to quiet thirst.

For the prevention of nausea he recommends the juice of acid
pomegranates, lemons, etc., or a decoction of parsley or sweet cicely
(_cerfolium_). The traveler should endeavor to sit with his head
erect, should avoid looking around, but maintain his head as immovable
as possible, and support himself by a firm grasp upon some beam of the
ship. Some sweets may be sucked, or he may chew a few aromatic seeds.
If vomiting ensues, acid or sweet pomegranates, figs or barley-sugar
(_penides_) may be taken sparingly, but no food should be ingested
until the stomach is thoroughly quieted. Then the patient may take a
little _stomatichon_ or _dyantos_, and a small portion of digestible
food. As the diet must necessarily consist largely of salty food and
vegetables, these should be cooked in three or four different waters,
and then soaked in fresh water. A little aromatic wine will also
benefit the patient, and a few aromatic seeds chewed in the morning
are also of service.

The effect of the foul odors of the ship may be combatted by the use
of aromatic electuaries, "which comfort the heart, the brain and the
stomach." The patient should be removed to some quiet portion of the
ship, as distant as possible from the channels for the discharge of
the bilge-water, and short walks upon the upper deck will contribute
to convalescence. Frequent changes of clothing will palliate the
annoyance of fleas and pediculi. Drinking water may be purified by
aëration, or by straining, boiling and subsequent sedimentation and
removal of the sediment by filtration through fresh and clean sand.
For the wealthy, the water may be distilled in an alembic, if such an
apparatus is obtainable. Avicenna says that bad water may be corrected