In the above paragraphs attention has been directed particularly to the nutritive and economic properties of food. It must not be considered that mere nutrition is the sole object of foods, especially for man. It is the first object to be conserved in the feeding of domesticated animals, but is only one of the objects to be kept in view in the feeding of man. Man is a social animal and, from the earliest period of his history, food has exercised a most important function in his social life. Hence in the study of food and of its uses a failure to consider this factor would be regrettable. For this reason it is justifiable in the feeding of man to expend upon the mere social features of the meal a sum which often is equal to or greater than that expended for the mere purpose of nutrition. This part of the subject, however, belongs especially to the kitchen and dining room, and, therefore, will not be discussed at greater length at the present time. It is believed that a more careful study of the food he consumes will benefit man in many ways. It will lead to a wider public interest in the problem of the purity of food and the magnitude of the crime committed against mankind in the debasement, adulteration, and sophistication of food articles. This study will impart to the social function of food an additional charm, in that the origin and character of the material consumed will be known and the properties which they possess for nourishing the body understood. This will enable man, as a social animal, to so conduct himself at table as to secure the greatest possible pleasure and social benefit therefrom and at the same time avoid any injury which ignorance might permit and invite. It may appear that the inartistic treatment of a subject of this kind, as indicated in the following pages, is not one which is calculated to excite any sympathetic interest or appeal to the natural desire for literary and artistic expression. Yet the importance of the subject is so great as to warrant the experiment of presenting the matter in this form rather than in any more elaborate and connected way. DEFINITION AND COMPOSITION OF FOODS.