SECRETARY'S REPORT. 251 



When we look at our clay soils, richer than most others in the 

 materials of which plants are made, but in a good degree locked up 

 from use by their cohesiveness, and needing only mechanical treat- 

 ment and weathering — thorough pulverization and mellowing, to 

 become highly productive, who will say that mechanical science may 

 not yet do as much for these, as chemistry may do to fertilize sand 

 barrens ? 



Soils having been originally formed by the exposure of rocks to 

 atmospheric influences, and their fertility being increased much in 

 proportion to their farther exposure to the same influences, these 

 having the effect to render soluble, and therefore available, their 

 mineral constituents, who will say that some economical application 

 of power may not yet be discovered, which, in the manner indicated, 

 shall add materially to the fertility of all soils, and accomplish as 

 much or more for agriculture, than chemistry can do ?• 



The relation of Geology to agriculture, grows out of the flict that 

 soils which cover the earth are the broken down or disintegrated 

 particles of the rocks of which the whole originally consisted. There 

 is a great diversity between soils originating in the primary, secon- 

 dary, tertiary, diluvial and alluvial formations, and a knowledge of 

 the nature of these formations will assist very considerably in form- 

 ing an intelligent estimate of the character and value of soils derived 

 therefrom, but alone, it is insufficient, and chemistry offers her aid, 

 not only in estimating the general character of a soil, but in revealing 

 its elementary constituents and inherent properties. It is the prov- 

 ince of this science, also, to analyze plants and ascertain their ele- 

 ments ; to determine the sources whence they derive their food ; to 

 tell us of what that food consists, and in a word, to reveal the laws 

 which determine the fertilization or sterilization of the soil. Chem- 

 istry has already accomplished much for the farmer, and bejond all 

 doubt, it is destined to do vastly more in time to come. Its present 

 imperfect condition is not to be wondered at, considering its very 

 recent date. The first actual contact of chemistry with agriculture 

 is said to have taken place within the memory of many living, when 

 the question svas submitted to Sir Humphry Davy, whether it were 

 better to employ the dung of animals for manure in a fermented or 

 unfermented state. The experimental researches of this eminent 

 father in chemistry, which were instituted with a view of solving 



