70 ON INCREASING THH GROWTH 



On the best time for applying manures, and on the 

 quantity in which they are to be used, practical ex- 

 periments must decide. Climate, soil, situation, and 

 many other circumstances demand various modifica- 

 tions, which can only be ascertained and established" 

 by experience. In the first respect it must be kept 

 in view, that plants require the most abundant nour- 

 ishment at the time of most vigorous growth. 

 Hence it must not be withheld from them from the 

 commencement to the blossoming, and in grain up 

 to the time in which it shoots into ear, if the highest 

 development is to be attained. 



On the means we possess of improving a manure, 

 hastening its action, and preserving its power, we 

 shall speak when we treat of the several kinds of 

 manure. 



It may be desirable, in conclusion, to group to- 

 gether in a preliminary view the best-known mate- 

 rials for the formation of manure which are at the 

 service of the agriculturist, in such a way that prac- 

 tical men may derive some advantage therefrom. 

 This could be accomplished by arranging them ac- 

 cording to their chemical constituents ; for this would 

 be identical with classifying them in conformity with 

 their operation, inasmuch as the latter depends upon 

 their chemical elements. In this attempt we unfor- 

 tunately come into collision with difficulties of an 

 insurmountable kind. The greater number of ma- 

 nures are complicated mixtures of three, four, five, 

 six, and more elements ; — which is the most impor- 



