JOHN P. NORTON'S ADDRESS. 567 



can say of how many substances it is made up, what are their 

 properties, and how much there is of each. When we thus 

 analyze soils chemically, we find a great variety in their com- 

 position, but are soon able to settle down upon some definite 

 rules. Very fertile soils, when we collect them together from 

 all parts of the world and analyze them, are found to have an 

 extraordinary similarity in composition. There are some eleven 

 or twelve substances that are always present ; not by any 

 means in the same proportion, but in at least appreciable quan- 

 tities. We thus have a standard of fertility. If in pursuing 

 our analyses, we come to a soil in which there is a scarcity 

 of some two or three of these substances, we shall invariably 

 find on inquiry, that such a soil needs occasional supplies of 

 manure. If we come to another in which a number are ab- 

 sent, or greatly reduced in quantity, that soil will certainly 

 prove barren. 



Thus the farmer has a simple rule laid before him. If cer- 

 tain substances are present in a soil, that soil when properly 

 cultivated will yield him heavy crops ; if some of these sub- 

 stances are wanting, he must supply them, and if many of them 

 are absent, he must consider whether he can profitably make 

 up the deficiency. These substances must be in the soil be- 

 cause they are needed to form the plant ; an analysis of the 

 plant shows this fact, and makes the connection between the 

 two at once apparent. The plant will not thrive upon one or 

 two of the articles that it requires for food, it must have all j 

 hence the necessity of them all in the soil. The absence of 

 only one, is sometimes fatal to a crop. 1 remember a case in 

 point as to the straw of oats. This straw, and indeed all of 

 the straws, owe their stiff'ness and elasticity to the presence of 

 a substance called silica, which usually abounds even in bar- 

 ren soils. In this case, however, the oats were grown upon a 

 reclaimed bog ; they always grew up stout and large, but in- 

 variably broke down as soon as the grain began to fill out and 

 render the top heavy. An analysis showed, as compared with 

 a strong healthy straw, a very striking deficiency of silica. 

 For want of this, although everything else seemed to be pres- 

 ent, the crop always failed, or was greatly injured. 



