This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
Local Hot Bathing. Hot water may be employed locally by semicupium, coxaeluvium, pediluvium, maniluvium, fomentation, or cataplasm. For an account of these methods of application, the reader is referred to page 69. They act on the same principles as the general hot hath, but are much less powerful, and, with the exception of the semicupium, or half-bath, which is usually employed as a milder substitute for the general bath, and in cases where determination to the head or trunk is feared, are used less for general stimulation, than for their excitant effect on some one part or organ of the body, or for their revulsive influence.
Thus, the hot hip-bath is used to stimulate the uterus in amenorrhoea; and the hot foot-bath and hand-bath to act revulsively from the head or interior organs towards the extremities, whenever the latter are cold, and evidences exist in the former of active congestion without fever, and especially when gout or rheumatism has retroceded from the extremities, and it is desirable to restore it to its original seat. Hot fomentations, or hot cataplasms, are employed to relieve by revulsion either inflammation, spasm, or other irritation of interior organs over which they may be applied, or to stimulate the part to increased action, as when it is desirable to hasten a languid external inflammation onward to suppuration, and through this to a more speedy cure.
Another form of local application is the hot douche, or stream of water falling from a height, or directed with some force upon the part. This unites the effects of shock and pressure to the stimulant action of the heat, and proves sometimes more efficient than the simple application of hot water, in chronic rheumatic and gouty swellings, obstinate local palsies, and indolent tumefactions and indurations of inflammatory origin.