Hydropathy, like Hydrotherapy and Hydrotherapeutics, means the use of water in the treatment of disease, or in the prevention of the tendency to disease. Popularly, however, hydropathy has become so attached to a special scheme of water treatment that it will be used here in that sense alone; while hydrotherapy will refer to the less restricted and more scientific use of water as one of the many therapeutic weapons furnished by experience to the armoury of the practitioner of medicine. Water is the world's natural medicine. We find early mention of water as a curative agent, and its virtues are extolled by many of the classical writers—e.g. Hippocrates, Galen, Celsus, Musa, and Asclepiades. In the middle ages Aëtius, Alexander of Tralles, Paulus of Ægina, and Avicenna may be claimed as its advocates; while in more modern times Cardanus, Hoffman, Bernardo, Sir John Floyer, Dr Baynard, the Hahns, Tissot, Dr Smith, and Hancock deserve mention; as do also Paré, Lombard, and Perey in special reference to its use in surgery. By most of these men water was applied both externally and internally—internally chiefly as a cold drink in fevers; and it was on this point the battle raged chiefly, Boerhaave and others disputing hotly against the propriety of so administering it. To Dr James Currie (q.v.), a Liverpool physician, belongs the credit of introducing its use in fevers and febrile diseases. His book (1797) contains some most interesting information, and the records of a large number of experiments carried out to the best of his abilities, with the very imperfect thermometers then in use. His interest appears to have been originally roused by the success of Dr Wright in treating fever, both in his own case and that of others, on board ship, by the application of cold sea-water. Currie's work was translated into German by Michaelis, and spread his treatment far and wide, meeting with much favour and also with bitter hostility. Amongst its warmest supporters was Oertel, a teacher in Ansbach, who re-edited, or rewrote, many of the older treatises, and who probably had some direct influence on the man who really introduced a new era in treatment by water. This was Vincent Priessnitz (1799–1815), a Silesian farmer of Gräfenberg, who after considerable success in treating wounds and sprains in animals with cold-water bandages, had to treat himself, a horse having broken some of his ribs. Again successful, he continued the treatment whenever he could on any of the neighbouring peasants, and advanced the further step of using water internally; his fame spread, and he soon gathered an immense clientèle and achieved remarkable success. He showed great ingenuity in inventing, with the assistance of his patients, all sorts of new methods of applying water to every part of the body; and, though using water as his sole remedial agent, he very sagaciously employed hard exercise, fresh air, and a regulated plain diet as adjuvants. Unfortunately, being utterly ignorant of medicine, he taught peculiar ideas of disease, which he considered to be due to the presence in the blood of certain acrid humours which had to be diluted and extracted by means of water. He said the escape of these produced an eruption which marked the crisis; but as it is known that water applied continuously will produce such an eruption on even the healthiest skin, and as all the known facts of pathology are opposed to his doctrines, we are obliged to reject his theories even while his practice is admitted to be admirable. It is to this special system of water treatment that the term Hydropathy is now generally applied. There are, however, endless hybrid varieties in which one or other theory, or particular form of practice, is either specially rejected or adopted; so it must not be supposed that the foregoing statements apply absolutely to all hydropathists. Beyond cavil, however, the most scientific position to take up is that in which water is used as a remedial agent in every way, in which it has been proved to be useful, without restricting its use, or reading its results in the light of any theories, while at the same time care is taken to avoid all ill effects. This constitutes the system of Hydrotherapy, which obtains prominent notice in all modern books on therapeutics. Possibly the term might be improved, as heat in many cases seems to be the real agent, of which water is only the vehicle. Thermotherapeutics and Thermotherapy have been suggested as terms more scientifically correct. Water has often been abused, like every other good thing in this world; even an ice-water dyspepsia, due to too free indulgence in drinking iced water (but especially along with food), being not uncommon in America.
Water may be employed medicinally both internally and externally in its three forms—solid, liquid, and gaseous. For the external uses, see BATH; for its internal use with drugs in solution, see MEDICINE, and MINERAL SPRINGS. There is left for consideration here only its use internally as pure water. Absolutely necessary to the digestive process, it is essential to life, and requires rules for its advantageous use. Too large a quantity impairs digestion by so diluting the gastric and intestinal juices as to render them comparatively inert. The difficulty is to lay down definite rules for the right quantity, as this will vary with each individual in different surrounding circumstances, of temperature, amount of exercise, and quality and quantity of food. Personal experience and skilled advice must decide the quantity in each case.
As a general rule it is better to drink water about an hour before meals, as the gastric juice is then being prepared, and fluid will be thus supplied when most required. Every one with a weak digestion ought certainly to do this, and only drink a little hot water with food, as the stomach requires a considerable temperature to allow its physico-chemical reactions to be carried on successfully. Water is also very useful early in the morning and late at night as helping to flush out the stomach and bowels, dissolving and carrying off the waste materials which may have accumulated by the kidneys, lungs, and skin, the functional activity of which organs it much promotes. Where the evacuating power of the lower bowel is weak, or when piles are present, large injections of water, hot or cold as judged proper, are useful in clearing out the rectum and stimulating its coat. Ice internally or externally is very useful in checking hemorrhage and soothing irritability, as shown by vomiting or otherwise. As steam water is very useful in all forms of inflammation and irritation about the mouth, throat, or lungs, and often in such cases medication with various drugs increases its powers.
There are fifty hydropathic establishments in England, fifteen in Scotland, and only one in
Ireland. Most of these originally started with a full equipment for treatment, including a resident physician, bath attendants, and a complete set of baths; but many of the establishments now are merely high-class country boarding-houses. In a few, however, the hydropathist can still find all the usual requisites for correct hydropathic treatment. Amongst the best known of the old-fashioned houses are Smedley's at Matlock Bridge, Ben Rhydding, Ilkley Wells House, Malvern, and Southport in England; Cluny Hill near Forbes, Bridge of Allan, Melrose, Rothesay, and Crieff in Scotland; and St Ann's Hill near Cork, in Ireland. Among the magnificent modern establishments we may name those at Bath, Bournemouth, Buxton, Harrogate, Ulverston, Windermere, The Hall at Bushey near Watford, Moffat, Peebles, Pitlochry, Shandon, Dunblane, Craiglockhart near Edinburgh.
See Claridge, Cold Water Cure (1841); Graham, Gräfenberg (1843); works on the Water Cure by Gully (1842-63), Johnson (1843), East (1850), Dunlop (1873), Smedley (1879), Braun (Eng. trans. 1875), and in German by Munde (1877), Runge (1879), Anjel (1886), with other works cited in the thirty pages of bibliography appended to Dr Winternitz's article on 'Hydrotherapeutics' in Von Ziemssen's Handbook of General Therapeutics (vol. v. 1886).
• Hydrophis. See SEA-SNAKE.