I shall not be so minute either in the description or treatment of the scurvy, as of the preceding diseases. A detail of this kind would lead to unnecessary prolixity and repetition; for the prevention and cure of it consisting in diet rather than medicine, have been fully handled in the former parts of this work; and the subject, in the descriptive as well as the practical part, has, in a manner, been exhausted by Dr. Lind. With regard to the theoretical part, I refer the reader to the ingenious treatise lately published by Dr. Milman.

It has appeared that the principal source of scurvy is a vitiated or scanty diet, and that it is very much promoted by cold, moisture, filth, sloth, and dejection of mind. Hard labour has been assigned by some as a cause; but this is not conformable to my observation in general, and what has been related to have happened in the Conqueror118, more particularly led me to be of a contrary opinion.

The principal differences of the symptoms of the scurvy in hot and cold climates, so far as I have observed, are, that in the former the livid hardness on the extremities is an earlier symptom, and in the latter the gums are sooner affected, and the difficulty of breathing is a more frequent and more uneasy symptom. This difficulty of breathing is one of the most fatal symptoms, and is most frequent in those cases in which there are the fewest external marks of the disease, and is probably that form of the complaint which attacks a vital part by a sort of translation from the extremities.

There is a remarkable symptom sometimes attendant on this disease which has escaped authors, and is mentioned in Mr. Telford’s Report, page 23. This is the nyctalopia, or weakness of the eye-sight, which was also common in the garrison of Gibraltar119, among those who were affected with the scurvy, a disease that prevailed much during the late siege of that place.

With regard to the cure, enough has been said in the preceding parts of this work to prove that fresh vegetables are the most effectual antiscorbutics. I shall here mention a fact farther in proof of this, which has not before been taken notice of. When the fleet arrived at Barbadoes in May, 1781, part of the soldiers, who served as marines, were affected with the scurvy, and being sent to the army hospital, where, at that time, no fresh animal food was allowed, they recovered much faster by being confined to vegetable articles, than the seamen who were fed upon fresh animal food without any fresh vegetables.

It has farther appeared, that there is something in a particular class of fruit of the lemon and orange kind, which far surpasses every other remedy, whether dietetic or medicinal. Numberless instances have occurred, in the preceding part of this work, of men having recovered at sea from using the juice of this fruit alone, even under all the inconveniences of a sea diet. When the juice is intended to be kept for a length of time, it should be expressed and bottled, a small quantity of spirits being added to preserve it for if fire is used in preparing it, as in the form of a rob, I know for certain that its virtues will be thereby very much impaired. It is very difficult to say upon what principle these fruits act, for no sensible effects are produced by them except a small increase of some of the secretions.

It ought to be mentioned here as a fact of great consequence, though very little known, and never, I believe, published before, that the juice of limes and lemons is the best detergent of any external application that has yet been tried in scorbutic ulcers. Nothing was found so effectual in preventing these from spreading, and in disposing them to heal, as an emollient poultice with120 lemon or lime juice sprinkled on its surface; or it was applied by soaking in it the lint with which the sore was dressed, and also as a lotion, in which case it was used diluted with two or three times its quantity of water; for if used pure, it was found too irritating, and was apt to bring on a fungous disposition. This precaution is particularly necessary with regard to limes, the juice of which is a much more concentrated acid than that of lemons. Mr. Lucas, surgeon of the Conqueror, favoured me with several valuable remarks in proof of this practice. A poultice was always found a good application in these cases, by its power of absorbing the acrimonious discharge, which would otherwise irritate the neighbouring parts. I have been informed by a navy surgeon, who served in the former war, that he has known the most obstinate ulcers cured by applying a paste of oatmeal and water, the surface of which was sprinkled with Goulard’s preparation of lead.

The fleet was furnished with essence of malt; but its powers were so inconsiderable, that some of the surgeons denied that it had any. In trials, however, that were made in an early state of the disease, it was found to have a sensible effect in checking and removing it. It was also found of evident use in the bad ulcers so apt to arise in scorbutic habits, and in this intention was superior to the Peruvian bark as an internal alterative. Indeed, in those ulcers that were truly scorbutic, the bark was found to be of very little use; and, next to what has been already mentioned, joined to the advantages of diet, opium was found of the greatest service in disposing these, as well as all other ill-conditioned sores of hot climates, to heal.

I have mentioned the scorbutic habit as distinguished from the scurvy, but there seems to be no difference except in degree; for a person may be laid to labour under the disease before it betrays itself by any obvious symptom, and it must have gathered a certain degree of force before visible symptoms are produced. The chief mark of this latent and incipient stage of the disease is that incurable state of ulcers that has been mentioned, whether they appear spontaneously or in consequence of slight accidents. There is another mark of this scorbutic habit which is not mentioned in any description of the disease I have ever seen. It is a soft, indolent tumour which arises under the skin on a part which has received a small blow, or contusion, so slight as not to break the skin. It most commonly appears about the elbow or fore-arm, and generally disappears without any inconvenience, what it contains being absorbed. A surgeon, who opened one of them, (a practice, however, not to be approved of) informed me that it consisted of fluid blood. We may also reckon a languor, or sense of weight, as one of those marks of scurvy which occur before the more obvious symptoms appear.

In this state of the disease, the articles of lesser powers, such as malt and melasses, may be of service by preventing its farther progress, or the appearance of actual symptoms, and by restoring the constitution.

In some of the early stages of this disease the effervescing mixture of acids with fixed alkali may probably also be of use. I never could perceive any sensible benefit in those cases in which I tried it, though some of the gentlemen of the fleet reported to me that they thought it of service.

There is no article of the Materia Medica yet known that possesses any considerable power over this disease without the assistance of proper diet. With this assistance, however, it is found, that whatever tends to increase the fluid secretions, hastens very much the recovery of the scorbutic patient. I have observed a very striking instance of this in the effects of a spontaneous diarrhoea; for I have seen those hard livid swellings on the legs, that form one of the most constant symptoms of this disease, almost disappear, and the hams, from being contracted, become flexible in the course of twelve hours after the purging came on. I have endeavoured to imitate this with purgatives, but never with the same effects as the natural looseness. A free flow of urine is also found to promote the recovery, and vinegar of squills is one of the most effectual medicines in this intention. It is likewise of singular service to excite sweat; for an obstruction of perspiration seems to be one of the principal constituents of the disease. The goose skin, which is an early and constant symptom of this disease, seems to be owing to a constriction of the exhaling vessels. Dover’s powder has been employed with advantage as a sudorific, with decoction of the woods drank warm, and plentiful warm dilution. Camphor, combined with nitre, has been found one of the best remedies, and it acts both as a diaphoretic and diuretic.

Such external applications as relax the skin are found also to forward the cure. The contraction of the hams and the livid hardness of the calves of the legs are relieved by emollient cataplasms. Burying the legs in the earth, which has a sensible good effect, seems to act on the same principle, for it makes the parts sweat profusely.

There can be no doubt that in the scurvy there takes place in certain parts of the body a stagnation of the humours in the small vessels, particularly of the lower extremities, and that it is to this circumstance that the livid hardness of the fleshy parts of the legs is owing. The effect of medicine in removing this, must be to restore the action of those torpid vessels, so as to bring the stagnated fluids again into circulation121 Purgatives seem to act upon it as they do in the dropsy, by exciting absorption. The irritation of the bowels and their increased secretion thus affecting the minute vessels in all parts of the body, is the result of that sympathy or balance established between every part of the system, in order to support the harmony and effect the purposes of the animal oeconomy.

It has long appeared to me, that the scurvy is owing rather to a defect of nourishment than to a vitiated state of it. In fact, that sort of food which is supposed most commonly to induce the scurvy, is, in most cases, not putrid, but is in an unnatural and depraved state by being drained of its juices, which run off in brine; and perhaps some of the more subtile and nutritious parts are wasted by evaporation. It is not found that salt of itself has any effect in inducing the scurvy, and indeed it can be induced under a state of diet in which there is no salt, as we know from some instances quoted by Dr. Lind; and some cases are related by Dr. Monro and Dr. Milman, in the Medical Transactions, which are in proof of the same opinion. But the case most in point to prove that it depends on a defect of aliment, is that of Dr. Stark, who, by way of experiment on himself, reduced his diet to the least quantity he could subsist upon, and was thereupon affected with the symptoms of the sea scurvy. I have also known some symptoms of it arise in old people in consequence of long abstinence, owing to the want of appetite.

It would appear that the aliment we take in acts in two ways in increasing the vigour of the body. First, by assimilation, whereby it affords the matter of which the solids of the body are made, in order to carry on growth in youth; and to repair the waste of parts in adult age. A very small quantity of matter is necessary for these purposes; and as a proof of it, we see people supported equally well with very different quantities and qualities of food. Secondly, Food is necessary as a stimulus, either by a power it has of soothing the nerves of the stomach, and the other surfaces to which it is applied, or by its volume in distending the intestines and blood vessels. It is upon this principle that luxury renders the great quantities of food we take in necessary; and those species of food which satisfy most by their stimulus are by no means such as are the most nutritious. It is also upon this principle, that in cases of accidental hardship from want of food, or in barren and inclement countries where food is scarce, the body is supported, in some measure, by what contains little or no nutritious matter, such as pure water, or the bark of trees powdered and kneaded into a sort of bread, as we are told of the inhabitants of Lapland.

There are other familiar and well-established facts, which prove, that either from the influence of disease, from habits of life, or the nature of particular animals, life can go on for a length of time with little or no aliment. This is the case in fevers, in sea-sickness, in certain singular cases that have been recorded122, in torpid animals, and in animals of cold blood. Though a man in health will die if deprived of food for a very few days, it does not follow that this is owing to the want of matter to repair the waste of the body. The craving for food, and the faintness from long abstinence, arise from the want of the accustomed stimulus, especially in those who are used to live well; and a person feels himself most refreshed by food and drink when newly taken in, and before it can be applied to the purpose of nutrition.

As there is a continual waste and decay, however, both of our fluids and solids, some degree of reparation is absolutely necessary, especially to animals of warm blood; and such ingesta as would give the stimulus of food, without being possessed of any nutritious principle, would indeed continue life for a certain time; but disease would ensue. The provision used at sea answers, in a great measure, to this description; for unless the powers of digestion and assimilation are remarkably strong, salt beef and biscuit, which have been long kept, do not contain much more nourishment than saw-dust, or the bark of a tree, and the disease induced by this diet is the scurvy.

The nature and symptoms of the scurvy countenance this opinion: for as the means of renewing the animal matter of our bodies is withdrawn under this course of diet, nature, in consequence of an accommodating principle, observes a sort of frugality, and the animal oeconomy adopts such measures as may be productive of the least possible waste and corruption of the fluids. Accordingly all the secretions become scanty; and, in particular, one of the first symptoms of this disease is a suppression of perspiration, as appears by the goose-skin that attends it. There is a paucity of urine. There is also a great languor in the circulation, which may be considered either as a means adopted by nature to prevent that vitiated and effete state of the fluids which a brisker action might induce; or it may happen from a want of that due supply of nourishment necessary to produce a vigorous action of all the functions.

We have a proof of this general languor not only from the great aversion to motion, and the great disposition to syncope, but from the inspection of the dead body, from which it appears that the whole circulating system, being more flaccid and less elastic, is subject to preternatural distention. The heart is accordingly found enlarged in bulk, the size of the cavities being increased; and in the extremities, where the circulation is naturally most languid, the small vessels carrying the colourless part of the blood, are so far enlarged as to admit the red part of it, as appears by the livid colour; and where this is the case, these vessels being unable to carry on the circulation, a stagnation ensues, as is evident in those livid appearances most common about the calves of the leg, which feel like a hard cake. I have examined those parts in the dead subject, and found a want of fluidity in the contents of the vessels, but could not discover any thing like eechymosis; from which I concluded that the colour was owing to an error loci, and the hardness to stagnation and coagulation of the fluids, and a want of action of the vessels.

The incurable state of ulcers, so common in this disease, is also what we might expect from the defect of fresh assimilated juices; for where a breach is made, either by nature or accident, in the solids, particularly of the extremities, the proper suppuration is prevented by the depraved state both of the fluids and vessels; and we cannot expect that renewal of solid parts in which healing consists, where both the instruments and materials of its formation are so defective.

I shall conclude what I have to say on this subject, by shortly considering whether or not this disease is ever contagious.

There is something in the nature and history of the scurvy that would lead us at once to pronounce that it is not infectious; for the external causes on which it depends are so obvious, and seem so adequate to account for its appearance and prevalence upon certain occasions, as at first sight to exclude every other external cause.

But it seems extremely unphilosophical to deny the reality or possibility of any thing in Nature, from our supposed knowledge of the means and causes she employs, particularly in a branch of science so obscure as the animal oeconomy. Could we, therefore, prove the point as a matter of fact, it would be in vain to deny it, from our fancied acquaintance with Nature’s modes of operation.

The facts which give a suspicion of the scurvy being infectious are, 1st, What is related by Dr. Lind, that the sea scurvy spread at one time from the naval hospital to the people of the adjacent country. 2dly, There occurred several instances, in the first part of this work, of this disease prevailing to a much greater degree in some123 particular ships than others, though upon the most accurate inquiry there was found no difference in the diet, or any other external or predisposing cause adequate to account for this. We can conceive, that those ships having accidentally a few men, whose constitutions were remarkably predisposed to this disease, might catch it earlier than in other ships, and communicate it to the rest of the crew.

The only practical inference that would lie from the establishment of this fact would be, that when the disease begins first to appear, the men affected should be separated from the rest; and this is a good practice, whether this opinion is true or not; for such men ought to be put in one mess, in order that they all may live upon the same antiscorbutic articles of diet, and that they may more easily be debarred from the use of their common provisions, of which this disease does not make them lose the relish.