2 POULTRY CULTURE 



is occasion to consider them. It is from inability to do this that 

 poultry keepers who have become proficient in a special line 

 carried on under particular conditions so often make serious mis- 

 takes when conditions change or when they make departures from 

 methods with which they are familiar. As it is not possible for a 

 student during the period of a course of instruction, or even in 

 some years of practice, to acquire such acquaintance with all phases 

 of the subject empirically, a textbook must so present the subject 

 that historical fact and description and discussion of materials and 

 methods will, as far as possible, compensate for lack of experience. 

 Thus a textbook must especially emphasize many things that do 

 not strongly appeal to the novice most interested in what he can 

 immediately put into practice. 



The limits of instruction. The quantity of theory of this subject 

 which one may assimilate and the rate at which principles may be 

 mastered vary with the nature of the matter as well as with the 

 preparation and capacity of the student. 



Thus a thorough knowledge of the principles of poultry-house 

 construction may be acquired from books alone in a comparatively 

 short time, and with knowledge so acquired a person with a little 

 skill in carpentry may design and build a house in every respect 

 as good as any experienced poultryman would make, provided 

 always that the principles are understood and correctly applied. But 

 in feeding, a working knowledge of principles is rarely, if ever, 

 acquired without practice. Practice in feeding sufficient to assist 

 to a good understanding of principles can be had in a few months 

 or even in a few weeks. In such matters as breeding, real practice 

 cannot be given in connection with courses of instruction. Long- 

 course students who are familiar with the general principles of 

 breeding and their application to domestic animals should have no 

 difficulty in understanding their applications to poultry. The short- 

 course student who lacks this preparation, and who has had no ex- 

 perience in breeding, gets at best but a limited appreciation of 

 principles from the condensed statement of them appropriate in 

 a general treatise on poultry. The student at home is even more 

 heavily handicapped. As a rule such an understanding of the 

 principles of breeding as every breeder should have is only acquired 

 after thorough study and long practice. 



