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.