INTRODUCTION 3 



and grows by experiments. An experiment is a question put to 

 nature. It matters not what theories or lack of theories are be- 

 hind the experiment, if the question is carefully and skilfully 

 put, and if we see with a clear eye, not dazed by prejudgment, the 

 answer will advance our knowledge. The knowledge of how ex- 

 periments have been planned helps us to plan them for ourselves ; 

 the knowledge of how a certain problem has been solved keeps us 

 from regarding the knowledge so secured as dogmatic, and gives 

 us an opportunity to test it for ourselves if we so desire. The 

 scientific investigator cannot accept the conclusions of others at 

 their face value; he must examine the evidence offered, and 

 satisfy himself that the evidence justifies the conclusion. 



Division of the Subject. Agriculture falls naturally into two 

 divisions the production of plants, and the production of 

 animals. Usually in the case of plants, only a portion of the 

 plant is desired, such as the grain ot wheat or corn, the tubers 

 of potatoes, etc. The remainder is considered as a by-product 

 and such disposition is made of it as appears feasible. The dis- 

 position of the by-product has considerable effect upon the 

 fertility of the soil, or the profits of agriculture. In some cases, 

 as in the preparation of hay, the entire plant is utilized. In other 

 cases, by-products result in the preparation required before the 

 product can be placed on the market, such as threshing of wheat 

 or rice, husking or shelling of corn, etc. 



The study of plant production involves a study of the condi- 

 tions which are favorable to plant life, the composition and prop- 

 erties of the atmosphere and the soil, the maintenance of soil 

 fertility, fertilizers, methods of soil treatment, etc., as well as 

 the composition and properties of the plant products, and a study 

 of such chemical changes as are involved in their production or 

 preparation for market. 



The study of animal production involves a study of the prin- 

 ciples of animal growth and nutrition, the composition and prop- 

 erties of feeding stuffs, their preparation or preservation, and the 

 methods of feeding for different purposes, such as meat, milk, 

 wool, etc. 



