334 ANALYSES OF NOVA SCOTIAN SOILS.— HARLOW. 



Again, Lemberg found that leucite, KAlSi206 in NaCs 

 10% solution gave Nax4.1Si206 and KCl; also that feldspar 

 with ordinary soluble salts gave similar exchange of basic 

 elements. These are the changes which must be taking 

 place in our Bay of Fundy waters, and of which Cameron of 

 the U. S. Bureau of Soils says "It is to be regretted that 

 there are not more precise data available as to the stability 

 of the various rock forming mineral species in contact with 

 solutions of the more common and readily soluble salts at 

 ordinary temperatures since such data would be of great 

 value for geological, mineralogical and soil studies." 



If the tide water with its dissolved matter acting on the 

 newly brought down rock debris presents a wide range of. 

 possible new substances, how much more complex will be 

 the action in a field, marsh or upland where we have organic 

 matter, more or less decomposed; soil atmosphere, living 

 plant organisms as bacteria, molds, ferments.; animal forms 

 as protozoa, in addition to the rock residues bathed in the 

 soil moisture which is a solution of products yielded by many 

 components and in equilibrium or nearly so with the solids 

 or gases with which it is in contact. 



Scientific Agriculture is the handling of this hetero- 

 geneous mixture so as to give, with a minimum of labor, the 

 greatest crop return, and yet be able to pass it over to the 

 next generation, not in an exhausted condition, but per- 

 manently improved. It is based on knowledge which is far 

 from complete. Our marsh soils in some places are "run 

 out," giving one half ton of hay per acre. Why is this? 

 We usually say that the available plant food is used up; on 

 the other hand the Bureau of Soils at Washington has, within 

 the last ten years, advanced the Toxin theory which is, that 

 plants in exhausted soils are like human beings in a room, 

 the air of which is polluted by excreted substances, disagree- 

 able and sickening; that the growing plant excretes poisons 

 which, if allowed to accumulate in the soil, kill the plant; 



