The proper time for taking breakfast depends a good deal on the individual constitution and mode of life. Those who eat supper ought not to breakfast till one or two hours at least after rising; but persons who dine late and eat nothing afterwards require breakfast sooner. Individuals of a delicate frame are often unable for either bodily or mental exertion in the morning, and are invariably injured by any attempt at exercise or serious thinking before breakfast; but strong healthy persons and those in whom digestion is naturally slow, may enjoy and even be benefited by two or three hours of activity before their morning meal, especially if accustomed to eat supper. Experience is the only sure guide in such cases, but, as a general rule, breakfast about half an hour or an hour after rising will be found most beneficial; and those who rise very early will do well to follow the French custom of taking a cup of coffee or tea, and bread, on getting up, and reserve their appetite for a more substantial breakfast three hours later. This is an invaluable rule for students, who often seriously impair their digestive functions by studying for hours in the morning, regardless of the craving of the system for nourishment and support. If exposure of any kind is to be incurred in the morning, whether to the weather or to the causes of disease, it becomes a matter of much importance that breakfast or some substitute for it, should be taken previously. It is well known that the system is more susceptible of infection, and of the influence of cold, miasma, and other morbid causes, in the morning before eating than at any other time; and hence it has become a point of duty with all naval and military commanders, especially in bad climates, always to give their men breakfast before exposing them to morning dews or other noxious influences. Sir George Ballingall even mentions a regiment quartered in Newcastle, in which typhus fever was very prevalent, and in which, of all the means used to check its progress, nothing proved so successful as an early breakfast of warm coffee. In aguish countries, also, experience has shewn that the proportion of sick among those who are exposed to the open air before getting any thing to eat is infinitely greater than among those who have been fortified by a comfortable breakfast. Where there is any delicacy of constitution, the risk is of course increased.