I should now proceed to enumerate the chief improvements made since that period, and which have enabled our ships to make so many successful circumnavigations, as in a manner to efface the impression of former disasters; but as I have mentioned the sickness most destructive to mariners, and against the ravages of which those preservatives have been mainly contrived, it may be proper briefly to explain its nature, and the rather as, unless among mariners, it is little understood.  First then, I would observe that the scurvy is not the ailment which goes by that name on shore.  The distemper commonly, but erroneously, in this place, called the scurvy, belongs to a class of diseases totally different from what we are now treating of; and so far is the commonly received opinion, that there are few constutions altogether free from a scorbutic taint, from being true, that unless among sailors and some others circumstanced like them, more particularly with respect to those who use a salt and putrid diet, and especially if they live in foul air and uncleanliness, I have reason to believe there are few disorders less frequent.  This opinion I submitted to the judgment of the society several years ago, and I have had no reason since to alter it.  I then said, contrary to what was generally believed, but seemingly on the best grounds, that the sea-air was never the cause of the scurvy, since on board a ship, on the longest voyages, cleanliness, ventilation, and fresh provisions, would preserve from it; and that upon a sea-coast, free from marshes, the inhabitants were not liable to that indisposition, though frequently breathing the air from the sea*.  I concluded with joining in sentiments with those who ascribed the scurvy to a septic resolution, that is a beginning corruption of the whole habit, similar to that of every animal substance when deprived of life**.  This account seemed to be sufficiently verified by the examination of the symptoms in the scorbutic sick, and of the appearances in their bodies after death***.  On that occasion I remarked, that salted meats after some time become in effect putrid, though they may continue long palatable by means of the salt; and that common salt, supposed to be one of the strongest preservatives from corruption, is at best but an indifferent one, even in a large quantity; and in a small one, such as we use at table with fresh meats, or swallow in meats that have been salted, so far from impeding putrefaction, it rather promotes that process in the body.

[* Diseases of the Army, part I. ch. 2.  Append.  Pap. 7.]

[** Woodall’s Surgeon’s Mate, p. 163.  Poupart.  Mem. de l’Acad.  R. des Sc.  A. 1’99.  Petit.  Mal. des Os, tom.  II.p. 446.  Mead on the Scurvy, p. 104.]

This position concerning the putrefying quality of sea-salt, in certain proportions, hath been since confirmed by the experiments of the late Mr. Canton, Fellow of this Society, in his Paper on the Cause of the luminous appearance of sea-water*.