10 SCIENTIFIC AGRICULTURE. 



mere inspection. If not a mechanic himself, the me- 

 chanic arts must be understood by those who furnish 

 him with plows and wagons and other farming im- 

 plements. The science of Physics, which treats of 

 the general properties of bodies, and the causes 

 such as light, heat, and electricity that modify these 

 properties, is also important ; and, finally, the farmer 

 ought to have some knowledge of Chemistry, in order 

 to understand the constitution of soils, and plants, 

 and fertilizers, and to enable him to adapt them 

 to each other, and, when necessary, to determine 

 what ought to be added to a soil to make it produce 

 a good crop. 



8. We do not mean to say that the farmer or 

 planter must be skilled in all these sciences, but he 

 should have at least a general acquaintance with 

 them if he would practise farming to the best advan- 

 tage. To the farmer, they are all profitable subjects 

 for study, because they are closely connected with 

 his profession, and are, in fact, the foundation upon 

 which the science of agriculture is based. 



9. Perhaps the most important practical results 

 to agriculture have been derived from the science of 

 Mechanics and that of Chemistry. The progress in 

 the mechanic arts is seen when we compare the 

 farming implements now in use with those of for- 

 mer times. The rough, uncouth wooden plow has 

 given place to various forms of neat, easy-running 

 plows partly or wholly of iron, and even these have 

 given place in some countries to the gang and steam 



