Simple baths do not irritate the skin so much as when combined with shampooing and wet packing and shower-baths, or when a vapour bath is made more efficient by friction and by the various manipulations of the Turkish or Russian bath. The result of such attacks upon the skin are seldom long to wait for. Sooner or later a continual redness appears, followed by burning or itching; then come pimples, boils, and pustules; and though in past times these eruptions were regarded as critical and beneficial we must now look on them in their true light, as simply the injurious results of the action of water. Hebra has used the warm bath with success in alleviating the pain and misery arising from extensive burns of the skin, and he has also used it for some of the more troublesome of the scaly and itching diseases of the skin. Although he seems more alive than most authors to the evil effects produced by the irritation of water in cases which are unsuited for it, he has, on the other hand, surpassed every one in the extensive and continuous use of warm water. He says, “I began with two hours, then advanced to days, and at last extended the duration of the warm bath from one to nine months. I find that people can eat, drink, and sleep just as well in a continuous warm bath as out of it; that nutrition, respiration, and excretion go on as before.” Hebra asserts that in the external use of water it is a matter of small moment whether we apply the water hot or cold to the part; that the water soon approximates in temperature to that of the part to which it is applied; and that in this matter the wishes and inclinations of the patient need alone be consulted. With regard to _salt baths_, we may remind the reader that they may be used either cold or hot, and that they may thus be used in almost all those cases (some skin diseases excepted) in which baths of hot or cold water are found useful. When salt is added to the water, the stimulating effect upon the skin is increased, and the bath may be considered by so much the more powerful. Sea water, natural salt waters, and even crystals of sea-salt, or common salt added to ordinary water, have so firm a place among popular remedies that it is almost superfluous to make any formal remarks upon them. It is perhaps in the treatment of scrofulous affections that sea bathing and salt water have their greatest reputation. The sea-bathing infirmary at Margate is too well known, and its work too highly valued to need any words of approbation from the author of this Primer. It is probable that the inhalation of sea-air has more to do with the successful treatment of scrofula than the bathing in sea water, although we have no wish to cast a doubt upon the efficacy in the treatment of such diseases of a systematic stimulation of the skin.