15. _Oatmeal_: This article cannot strictly be deemed a medicine, yet, as water gruel is frequently wanted, that of oatmeal I think the best; besides, it is excellent for making poultices, being of a softening and rich quality. But if it should be wanting, _pounded biscuit_ will answer the purposes. In regard to diet, I shall say more in its proper place. 16. _cinamon_: This is a necessary article at sea, as it is of a gentle astringent nature, together being very warming, and is undoubtedly the best of all the spices, where the bowels are weak. Its peculiar uses I shall speak more of hereafter, when I come to treat on loosenesses and fluxes, and such diseases where it is useful. 17. _Allum_: This astringent medicine is very useful for gargles, for scurvy gums, and various other uses. Burned allum (which may be done by exposing a piece on a fire shovel over the fire till it is bubbled up and become of a white cake) is an excellent medicine, for gently checking proud flesh in ulcers; besides which, it makes an excellent tooth powder. 18. _Chalk_, is as necessary an article as any medicine, and so useful is it in long voyages, that a ship should be well stored with it; for it is not only an excellent absorbent, and will stop fluxes, when made use of in decoctions for that purpose, but, makes also a great purifier of water, and thereby contributes greatly to the preservation of health; as I shall hereafter further take under a stricter consideration. 19. _Salts_: Glauber’s purging salts, is a medicine which has had many virtues ascribed to it; as a cooling purge it is very well, but further I cannot recommend it: An ounce, or an ounce and an half is the dose; and it will be best to dissolve it in a tea cup of water over night, so that it may be taken early in the morning, and worked off with drinking gradually some tea after every motion. 20. _Diachylon plaister_: _Take lytharge fine prepared one pound, oil of olive one quart, boil them over a gentle fire, putting into the pan a little water, stir it all the while, and take care it does not burn; continue boiling, till it becomes of a consistency of a plaister, and make it into rolls; which, according to art, is best done before it is quite cold, upon a wet marble slab, and wet hands, and then put up in paper, previously rubbed over with some soap, to prevent it from sticking._ There is not a medicine so generally useful for all hands on board, as this very plaister, in case of cuts, bruises, or sores of any kind; it is not only the medicine box that should be well provided with it, but every man on board, I advise to have a roll, and some spread on cloth in his chest; for in every little accident, a cut, a broken nose, or broken shin, &c. to which a seaman is liable, nothing is handier, and nothing is more beneficial than this plaister, as it will prevent inflammation and festering, heal it up, and prevent small sores from becoming great ones. 21. _Mercurial plaister_: