have leave to transcribe whatever I find to my purpose. The firft appearances are much the fame in the two diseases at land and at fea; but at fea they foon run to a much higher degree. Nothing is more furprifing than the malignity of this, as it were corrofive, poifon exerting itself fo far, that the fears of wounds, which had been many years healed, were often forced open again. Nay the callus of broken bones, which had been completely formed for a long time, was found diffolved, and the fracture feemed as if it had never been confolidated.

This malady was likewife accompanied with many other dangerous symptoms, particularly putrid fevers, pleurifies, the jaundice, an obftinate coftiveness, and, at the latter end, a difficulty of breathing. This last was found to be the most deadly of them all for it never was without fuch a faintnefs and weakness, that many expired upon the leaft motion, and endeavouring to get out of their hammocks, died before they could reach the deck.

Moreover, a strange dejection of the fpirits, with fhiverings, tremblings, and dreadful terrours on the flightest accidents, was fo conftant an attendant, that whatever difcouraged the fick never failed to add new force to the distemper.

Such are the ftrokes of this compounded calamity: and many more might be enumerated: but it is time. to proceed; and to inquire into the manner by which they are produced.

It is certain, that fuch bad diet as has been mentioned, will corrupt the blood and humours; but nothing is clearer from the whole history of this voyage, than this, that the air is, even more than any other

agent, concerned

concerned in bringing on the mischief *. It may indeed juftly feem ftrange, that the writers of phyfic fhould not have obferved fo remarkable a caufe; but they defcribed the land-fcurvy only. Nay, fo great was the efficiency of the aerial fluid, that even a warmer climate did not mitigate the fcorbutic virulency; neither did fresh provifions, and plenty of wholefome rain-water avail; although thefe are certainly of great importance in preferving the body from the fatal diforder. Of fo much confequence it is to refift the first approaches of an enemy.

Now, the manner in which the aforefaid caufes act, is this. Whoever understands the ufe of refpiration, and the way by which the feveral offices neceffary to life are performed by means of it, will readily comprehend how the fea-air acquires fuch noxious qualities.

To fet this in a clear light, it must be observed, that air entering into the lungs does by its gravity and elasticity press upon the blood circulating in the veffels there. The effect of this preffure is twofold; firft, a comminution and divifion of it into fmaller particles; fecondly, fome fubtile claftic matter paffes into the blood, and exciting in it an inteftine motion, difpofes and prepares it for the fecretions of feveral liquors, when, in its courfe round the body, it arrives at the glands contrived for the feparation of fuch and fuch juices.

Whatever therefore alters this gravity and elasticity, makes the air unfit for the purposes for which it was defigned. In the first place, moisture weakens its fpring; next, a combination of foul particles, fuch as are contained in the breath of many perfons croud* See voyage, p. 294.

ed

ed together, and fome perhaps diseased; then, the filthiness of water ftagnating in the bottom of the fhip; laftly, falts imbibed from the fea, fome of which may probably have proceeded from putrefied animals in that element, may infinuate themselves into the blood, and, in the nature of a ferment, corrupt its whole mafs. Neither is it amifs to add, that the animal fpirits themfelves muft neceffarily partake of the vitious diforder of the fluid, from which they are derived. This is plain from that unaccountable faintnefs, and weaknefs of the body, and dejections of mind, which, as we have before taken notice, accompany the other symptoms.

It is needlefs to fhew how all the enumerated complaints, and indeed many more, may follow upon fuch a difturbed state of things, efpecially when the other mentioned caufes concur. It may be very fatisfactory to put down the obfervations, which the above-named furgeons made upon the blood of their patients, and upon the diffection of dead bodies, in the feveral ftages of the distemper.

In the beginning, as it flowed out of the orifice of the wound, it might be feen to run in different shades of light and dark ftreaks. When the malady was increased, it ran thin, and feemingly very black, and after ftanding fome time in the porringer, turned thick, of a dark muddy colour, the furface, in many places, of a greenish hue, without any regular feparation of its parts. In the third degree of the disease, it came out as black as ink, and though kept stirring in the veffel many hours, its fibrous parts had only the appearance of a quantity of wool or hair floating in a muddy fubftance.

In diffected bodies, the blood in the veins was fo entirely broken, that by cutting any confiderable branch, you might empty the part, to longed, of its black and yellow liquor. extravafated, it was of the fame kind.

which it be

When found
And lastly,

as all other kinds of hæmorrhages are frequent at the latter end of the calamity, the fluid had the fame appearance, as to colour and confiftence, whether it was discharged from the mouth, nose, stomach, inteftines, or any other part.

The effects we mentioned of the violence of the fcorbutic humour being fo malignant as to open the fears of old wounds, and diffolve the calli of fractured bones, which had for a long time been formed, appear to many to be quite incredible; the rather, because, as they commonly fay, a bone thus reunited is ftronger in that part than in any other of the fame joint. This indeed, I dare venture to affirm, is not true in fact. The cafe is thus: A callus is no more than a kind of cementation made by filling up the fpace between the broken ends of the bone, with the nutritious juice from the part. This, when nicely examined, is found to be more porous, and to have lefs folidity, though the bone often appears bigger than the part above and below it; the fibres are fmaller, fhorter, and not fo regularly difpofed as in the natural texture. In fhort, a callus is an imperfect offification. For this reafon, when the nutritious particles themselves have acquired a corrofive acrimony, they may, like a menftruum, work upon and break the texture of this fuperadded cement. Which is indeed a moft furpri

fing phænomenon.

It is proper after all to obferve, as a confirmation VOL. II.

K k

of

which was immedi

The dreflings were

of this reafoning, that although the callus is diffolved by the difeafe, yet, upon the patient's recovery, it is gradually formed again, in proportion to his coming to a right habit of body. I have before me a remarkable infance of this kind. A failor had one of his clavicles fractured in December, ately reduced, and foon united. taken off in January, and he made use of his arm as before. In the following April, as he was fufpending h's body by the arms, the fame clavicle was difunited, and the callus gave way as at firft. He at that time complained of fome fymptoms of the fcurvy ; which daily increafed till June following. At that time he was carried afhore at the island of Juan Fernandez. The bandages being removed, the fracture appeared in the fame condition as when the accident first happened, without the least remains of a callus : notwithstanding the proper applications, he could not ufe his arm until the middle of October; the callus having continued more than three months in a flexible ftate. From that time, by the ufe of a vegetable diet, and living on fhore, he gradually recovered from the diftemper; the callus was confirmed, and his ufual strength returned.

But it is time to come to the cure; which will be, fifft to prevent the attacks; and in the next place, to remove the effects of this virulent evil.

The first care to be taken is of the diet. And here I must take the liberty to make fome obfervations upon the manner of victualling our fhips. The trials already made, as I have been informed, of Mr Lowndes's falt made from brine, prove it to be much preferable, for falting provifions, both flesh and fish,

to