[144] See the Treatise published by Dr. _Luc. Anton. Portius_ in 1686, _de Militis in castris sanitate tuenda_, _part._ ii. _cap._ vi. In this Book we have many useful Things mentioned relative to the Health of Soldiers. Where there are no such Conveniences for purifying the Water, what is used for Drink ought to be mixed with a small Proportion of Spirits, or Wine, or with Vinegar, or Cream of Tartar, when neither of the other two can be got; and if the Water be previously boiled, it will be so much the better. In Expeditions into warm Countries, where fresh Water is difficult to be had, a few Stills, with a proper Apparatus, ought to be carried out; and after a Landing is made, the Stills ought to be set to work for distilling fresh Water from Sea Water in the Manner mentioned by Dr. _Lind_[145]; and although a sufficient Quantity cannot be distilled for serving the whole Army, yet enough may be got in this Way for the Use of the Sick. [145] Dr. _Lind_ relates a Number of Experiments of his having distilled Sea Water in different Manners, as recommended by others; and concludes, that the best Way of getting fresh Water from Salt, is to distil the Sea Water by itself, without any Mixture; and he proposes having a Still Head to the Coppers or Iron Pots in which the Meat is dressed aboard a Ship. _Ibid. note to p. 84_, &c. When Men are very warm, after long Marches, and other hard Duties, in Summer; Officers should endeavour to prevent their swallowing immediately great Quantities of cold Water, and persuade them to wait a little till they cool; and at such Times, if Spirits can be got easily, to order a small Quantity to be mixed with the Water in each Man’s Canteen. Though the Abuse of vinous and spirituous Liquors is very destructive to the Constitution, yet these same Liquors, given in Moderation to Soldiers on Service, during the Times of great Fatigues, are some of the best Preservatives of Health. Spirits, for common Use, ought to be mixed with Water; and in the hot Climates made into Punch; though in very cold and wet Weather, and in damp Nights, a Glass of pure Spirits, given to the Men going on Duty, is of great Service; for it is always observed, that Men are much less apt to catch Diseases from being wet when they are upon a March, or at hard Work, than when they stand Centinels, or are upon Out-Posts where they move but little, or when they lie down in their wet Cloaths; and that they are less liable to be affected by the Weather after a hearty Meal, or drinking a Glass of Spirits, or some generous Liquor, than when their Stomachs are empty.