26 FARM DEVELOPMENT 



practical bearing upon plant and animal production, such 

 as heredity, variation, selection, and the development of 

 species, varieties or breeds. Some of the more general 

 biological sciences are botany, bacteriology, zoology, 

 entomology and breeding. 



Mathematics is the most exact of all the sciences. It 

 deals with the measurement and relations of quan- 

 tities, and by symbols and processes treats of numbers, as 

 in arithmetic and algebra, and of space, as in geometry. 

 Mathematics is applied to all the physical and biological 

 sciences, and is used in all industries and professions. 

 Like all the more practical subjects, the study of mathe- 

 matics not only develops mental vigor, but also gives 

 valuable facts. 



Physics, in its specific sense, deals with the phenomena 

 of matter, and with the energy which accompanies mat- 

 ter, excluding the phenomena peculiar to living matter, 

 biology, and the phenomena peculiar to elemental forms 

 of matter, chemistry. Physics treats of the constitution 

 and properties of matter, of mechanics, acoustics, heat, 

 light, electricity and magnetism. A study of the gen- 

 eral principles of physics, illustrated at every possible 

 point by its use in explaining mechanical contrivances, 

 soils, feeding and other questions in agricultural prac- 

 tice, is proving most useful as a means of general mind- 

 training and of acquiring useful facts. 



Mechanics treats of the phenomena caused by the action 

 of energy, or force, on material bodies. It considers the 

 phenomena of static bodies of matter with their latent 

 energy, and kinetic bodies with their dynamic forces 

 operating. Applied mechanics deals with the invention, 

 construction, care and use of all kinds of structures, 

 machines and devices. The people of the world are 

 housed, clothed, fed, transported and supplied with in- 

 formation and luxuries in far greater amount and with 

 far less cost of time and effort because of the development 



