If it be impossible for me to communicate sufficient information to enable each of my readers at once to determine beforehand the kind of diet which is likely to suit him best, it will give him at least some satisfaction to know, that, by observing personally what kind of food agrees best with his stomach and constitution, he may soon obtain the necessary information for himself. When we refrain from eating too much and at unreasonable hours, and are not conscious of any undue oppression or discomfort after our meals, but, on the contrary, feel light or refreshed, and, after a time, ready for renewed exertion, we may rest assured that the food which we have taken is wholesome and suitable for us, whatever be its nature and general effects. Whereas if, without committing any excess or other dietetic error, we experience the opposite sensations of oppression, languor, and uneasiness, we may be just as certain that our food, whatever its general character for lightness and digestibility, is not wholesome or suitable for us under our present circumstances. So that, with a little care and trouble, we shall rarely be at any loss to find out what we ought to eat and what to avoid; and, accordingly, it is notorious that indigestion from a wrong choice of food is induced at least nine times by wilful indulgence, for once that it occurs from errors originating in ignorance alone. If the proper _quantity_ of food be not exceeded, and the other conditions of digestion be carefully fulfilled, the risk of mischief from an erroneous choice of aliment will be greatly diminished. * * * * *