The mere reduction in the amount of food, however, would not have been sufficient in itself to cause the epidemic of scurvy. Scurvy will occur even with a copious dietary. Sailors who eat plenty of biscuit and beef are attacked, and others who are certainly not starved. The real predisposing cause is the absence of certain necessary elements in the diet, not the lowness of the diet itself. It is the want of vegetable acids in food that brings about the mischief. The authorities called in were not exactly right, therefore, in attributing the scurvy solely to the reduced diet. The siege of Gibraltar was quoted as an instance where semi-starvation superinduced the disease. Again, the scurvy prevalent in the low districts round Westminster was traced to a similar deficiency and the severe winter, also to the want of vegetable diet. This last was the real explanation; of this, according to our medical knowledge, there is not now the faintest doubt. Long enforced abstinence from fresh meat and fresh vegetables is certain sooner or later to produce scurvy. At the same time it must be admitted that the epidemic of which I am writing was aggravated by the cold weather. It had its origin in the cold season, and its progress kept pace with it, continued through the spring, actually increasing with summer. During the months of May and June the disorder was progressive, but the early part of July saw a diminution in the numbers afflicted. At this time the prison population amounted to about eight hundred.