SECT. LIII.—ON THIRST.
A protracted thirst may be supposed to be occasioned by dryness, or heat of the parts, by which liquids pass from the mouth to the stomach; and the natural cure of dryness is sleep, and of heat, watching. Some become thirsty from wine, or the heating nature of their food, in which case, the proper cure is cold drink. But some desire drink of a bad quality, as they do food corresponding to the prevailing cacochymy. I have known persons seized with unquenchable thirst, of which they died, who had eaten of the vipers called dipsades, and others who had got drunk upon old wine; and also persons on board of a ship, who, when their fresh water failed them, had drunk of sea-water, have all died. Febrile thirst may be mitigated, by pouring upon the head the coldest oil, or rose oil. But the best remedy for thirst is the seed of the black lettuce, chewed, or the liquorice; or, seed of the cucumber may be retained in the mouth. Give also the following pill, called adipson: Of garden cucumber, dr. viij; of tragacanth, dr. iv; dissolve the tragacanth in the white of fresh eggs, and when dissolved, add to the pounded seeds of the cucumber; and when softened, form pills, which dry in the shade. Give one of these pills to hold below the tongue, and drink the fluid of it as it dissolves. Give also, to swallow, the decoction of quinces, or of pears, or of medlars, or of the tendrils of the vine, or the juice of the pomegranate.
Commentary. The greater part of this Section is taken from Galen (de Caus. Symp. l. c.), who, as usual, handles the subject very philosophically. Oribasius treats of it in nearly the same terms as our author. (Synops. vi, 37, 38, 39.) Aëtius remarks that there are two causes of thirst, a want of humidity, or a redundance of heat. In fevers, then, both these causes cooperate to occasion thirst; for there is excess of heat originally, and dryness comes on owing to the fluids of the body being consumed by the febrile heat. (v, 119.)
The question was keenly agitated in the ancient schools of medicine, whether cold drink might be safely given in fevers. Hippocrates was a great advocate for this practice, giving his patients barley-water and acidulated draughts very freely at all periods. Asclepiades, on the other hand, as Celsus and Alexander inform us, forbade even to wash the patient’s mouth with water during the first stage of a fever. Celsus is disposed to hold a middle course between these opposite methods of practice. He particularly approves of washing the mouth and fauces frequently with cold water, because, as Erasistratus had properly remarked, these parts often required cold liquids, while the internal parts are not in want of them. Philumenus (ap. Aëtium) also strongly recommends gargles, but forbids cold drink freely until after the acme of the fever. Alexander informs us that the celebrated Archigenes allowed his patients the free use of cold water and acidulated drinks. He himself does not speak very decidedly for or against this practice, but, upon the whole, is disposed to think well of it, unless there be inflammation, hardness, or swelling anywhere. He approves, however, of cold applications externally: and, accordingly, directs us to apply to the region of the stomach a bladder filled with cold water, ice, or some cooling decoction.
Of the Arabians, Serapion expresses himself most decidedly in favour of cold drink. Avicenna forbids much to be given at a time. See also Haly Abbas (Pract. iii, 22); Alsaharavius (Pract. xvi, 14); Averrhoes (Collig. vii, 24); and Rhases (Contin. xxx.)
The pill mentioned in the end of the Section is from Dioscorides.
Prosper Alpinus represents the Methodists to have disapproved of the free use of cold water in fever. (Med. Meth. vi, 7.)
The highest of the ancient authorities, as for example, Galen, Avicenna, and Averrhoes, agreed in allowing wine, much diluted with water, in fevers. Galen says, the wine should be attenuant and of a light colour. According to Avicenna, wine thus plenteously diluted with water is preferable to plain water, as it promotes perspiration.
Fabius Paulinus gives an admirable exposition of the philosophical doctrines of the ancients on this subject. He remarks that there are three distinct species of thirst. The first is occasioned by the fauces and œsophagus being drier or hotter than natural. This state, if it supervene upon sleep, is to be cured by watchfulness, or vice versa. In the second, the veins over the whole body are filled with hot and acrid humours. In the third, the mouth of the stomach, lungs, or heart are preternaturally hot or dry. (Marc. Prælect. 315.)