46 THE SCIENTIFIC PRINCIPLES 



position of the milk yielded by cows, being deter- 

 mined. 



The chemistry of the malting process, the loss of 

 food constituents during its progress, and the com- 

 parative feeding value of barley and malt, have also 

 been investigated. 



Many of the results of the investigations above 

 enumerated have already been published, but a large 

 proportion as yet remains unpublished. 



As already intimated, I propose to rely largely on 

 the data supplied in the more than forty years of 

 investigation at Eothamsted ; in the field, the feeding- 

 shed, and the laboratory, in the lectures which it 

 will be my duty to give in this University, in elu- 

 cidation of the scientific principles of agriculture. 



In the first place, however, to give logical sequence 

 to what will follow, I shall devote a few lectures to 

 the question of the sources of the constituents of the 

 plants and animals which are the products of the 

 art of agriculture. Obviously, the soil, and the atmo- 

 sphere, are these sources. The subject of the origin, 

 the general characters, and the composition, of soils, 

 is a very wide one ; and many lectures might be 

 devoted to its discussion. But it is foreign to my 

 plan so to discuss it ; as to do so would seriously 

 trench upon the time which should be devoted to 

 the consideration of other branches of our enquiry. 



I shall next consider the effects of manures, ex- 

 haustion, and variations of season, on the amounts 

 of produce, and on the composition of the produce, 

 of different crops, the effects of fallow, and the 

 benefits arising from a rotation of crops. 



Subsequently, I propose to take up the subject 

 of the feeding of animals, for the production of meat, 



