PRACTICAL AND SCIENTIFIC BREEDING Science has been defined as the "know how" and art as the "do how." The man who works by art depends upon an unconscious judgment which is inborn or is acquired by long practice. The man who works by science may also have this artistic taste, but he tests its dicta by comparison with known facts and principles. The scientist not only looks before he leaps, but measures the distance and knows exactly where he is going to land. Breeding has for centuries been an art, but the science of breeding is so new as to seem a mass of contradictions to all except those familiar with the maze of mathematics and biology by which the barn-yard facts must find their ultimate explanation. The science of breeding may in the future bring about that which would now seem miraculous, but it is the ancient art of breeding that is and will for years continue to be the means by which the poultry fancier will achieve his results. In a volume the chief aim of which is to place the poultry industry, which is now conducted as an art, in the realm of technical science, it might seem proper to devote considerable space to the subject of breeding, That I shall not do so, is for the reason that while theoretically I recognize the important part that breeding plays in all animal production, for the practical proposition of producing poultry products at the lowest possible cost, a knowledge of the technical science of breeding is unessential and may, by diverting the poultryman's time to unprofitable efforts, prove an actual handicap. For the show room breeder the new science of breeding is too undeveloped to be of immediate service, or I had better say, the show room requisites are too complicated for theoretical breeding to promise results. For the commercial poultryman, I shall review what has been accomplished and state briefly the theories upon which contemplated work is based. The objects striven after in poultry breeding are: 1st: To create new varieties which shall have improved practical points or shall attract attention as curiosities. 2d: To approach the ideals accepted by fanciers for established breeds, and hence win in competition. 3d: To change some particular feature or habit as, to increase egg production or reduce the size of bantams. 4th: To improve several points at once as, eggs and size in general purpose fowls. This classification is really unnecessary, as the most specialized breeding involves consideration of many points. Breeding as an Art. The method by which breeds and varieties of the show room specimens have been developed is essentially as follows: The wonderfully different varieties of fowl from every quarter of the earth are brought together. Crossing is then resorted to, with the result that birds of all forms and colors are produced. The breeder then selects specimens that most nearly conform to the type or ideal in his mind.