TIMES OF EATING.--If we look to the exposition of the objects of eating already given in treating of appetite, it will be obvious that Nature intended us to regulate our meals by the demands of the system, and not to eat at stated hours as a matter of course, whether nourishment were required or not. If we are engaged in occupations which induce a rapid expenditure of material, or if growth is going on so fast as to require unusually ample supplies, food ought to be taken both more frequently and in larger quantity than when we are differently circumstanced; or, in other words, _food ought to bear a relation to the mode of life and circumstances of the individual_, and not be determined by a reference to time alone. In reality, however, the animal economy is constituted with so strong a tendency to periodical activity, that as great an approximation as possible ought to be made to fixed times of eating. In general little difficulty and much advantage attend the arrangement; because where the mode of life is regular and nearly the same throughout a whole class, the same waste will go on, and consequently the demand for a supply of nourishment in all the individuals composing it will be felt at nearly the same intervals, subject only to such variations as are induced by original differences of age and constitution. As regards each class, therefore, regularity in the recurrence of their meals is not less natural than advantageous; and it is only when we attempt to combine a given order of diet with different and even incompatible modes of life that Nature refuses to sanction the arrangement. So strong indeed is the tendency to periodicity in the system, that appetite returns for a time at the accustomed hour, even after the mode of life, and consequently the wants of the system, have undergone a change; and if not gratified it again subsides. Ultimately, however, it calls with too strong a voice to allow of its being thus disregarded.