The thin white fur which already had begun to appear on the tongue progressively increases in extent and thickness. The colour of the fur usually changes, as the disease advances, from a dirty-white to an ash-colour; but in this form of the disease the tongue always remains moist, and never becomes brown. This state of the tongue is almost always accompanied with thirst, but it is never urgent. There is always a loss of appetite. The bowels are generally constipated, and the secretions of the whole alimentary canal are vitiated. Thus we perceive that the progress of the disease consists in increasing mental and corporeal weakness; increasing pain in the back, loins, and limbs; increasing heat of skin, acceleration of pulse, and general febrile uneasiness, together with the occurrence of pain in the head, and progressive derangement in the functions of secretion and excretion. The fever in this mild form is now at its height. It remains stationary, or at least with very little change for an indefinite period, generally for some days. The cerebral affection does not increase beyond what has been described: there are no greater indications of disease in the respiratory organs, and the mucous membrane of the stomach and intestines does not denote any progressive advancement in disease. One of the most remarkable circumstances connected with the ordinary fever of this country, in the present day, is the uninterrupted and perfect continuity of its phenomena. As long as the febrile state remains, nothing deserving the name of a remission is in general to be perceived. Occasionally, it is true, a slight increase in the symptoms may be observed towards evening, especially in the heat of the skin; but even this is not common, and it is scarcely ever great enough to deserve the distinction of being called an exacerbation. Much less is there any regularity in the accession and decline of such excitement. In the great majority of cases not the slightest approach to an exacerbation and a remission can be distinguished from the commencement to the termination of the disease. Yet the older writers speak of these events as if they were as palpable as the paroxysms of intermittent and as constant as the return of morning and evening. There cannot therefore be a doubt that the character of the ordinary fever of this metropolis is greatly changed from the character of that which prevailed two centuries ago; and the circumstances which have contributed to produce this change will be considered hereafter.