=Manufacturing and commerce.= It is very much easier to build up a large business in the manufacture or the sale of articles used by poultry and pigeon keepers than to build up a large business as a breeder of domestic birds of any kind. As has been stated in connection with nearly every kind of bird mentioned in this book, a poultry keeper's operations are limited by the difficulty of keeping large numbers of birds continuously on the same land, and also by the exacting nature of the work of caring for them under such conditions. In manufacturing and commercial operations there are no such limitations. The possibilities of development depend upon the extent of the demand for the articles that are manufactured or sold, and only a small proportion of the employees need to be persons versed in aviculture. But in competition with other manufacturers or merchants those who understand domestic birds and know all the different phases of interest in them have a very great advantage over those who do not. =Legislation and litigation.= The rise of new industries creates new problems for legislators, executive departments, courts, and lawyers. An industry in which many people are interested eventually reaches a stage where it is profitable for lawyers to specialize to some extent in laws affecting it, and politic for legislators and administrators to do what is in their power to protect the interests of those engaged in it, and to advance those interests for the benefit of the whole community. A special field is opening for lawyers familiar with aviculture and with its relations to other matters, just as within a few years the field has opened to teachers and investigators. * * * * * The possible uses of a knowledge of aviculture to young people who are naturally inclined toward intellectual professions, art, invention, manufacturing, or trading have not been given for the sake of urging students to direct their course especially toward work connected with aviculture. The object is only to show those who take an interest in the subject that it is worth while to cultivate that interest for other reasons, as well as for the profit or the pleasure that may be immediately derived from it. INDEX Abbotsbury, old swannery at, 229 Africa, guinea fowl in, 202; ostrich breeding in, 235 African goose, 164; illustrated, 164 Age, of earth, 25; of fowls, 92; of geese, 169; of swans, 223; of ostriches, 232 Agricultural experiment stations, interest of, in aviculture, 308 Agricultural fairs, poultry exhibitions at, 292 Aigret of peafowl, 208 Albumen, formation of, in egg, 17 Alfalfa, 140, 236 American Wild Goose, 165; illustrated, 166 American Wild Pigeon, 241 Amherst Pheasant, illustrated, 214 Ancona, 64 Andalusian, Blue, 49, 64 Animal kingdom, place of birds in, 2 Animals, having bird characters, 1; predacious, prevent use of colony system, 107