160 



REPORT OF THE COMMISSIONER OF AGRICULTURE. 



Standard of natural fertility, varying within certain limits, according 

 to the character of the season and the management; which standard, 

 on a large scale, could practically neither be permanently reduced nor 

 increased by cultivation. Such lands are said to be " out of condition." 

 Of course it must bo borne in mind that these observations apply to 

 actual English farm practice, and the term must not be pushed to any 

 great extreme. 



ACQUIRED OR TEMPORARY FERTILITY. 



A land is said to be "in good condition " when by the application of 

 manure its permanent fertility is raised so as to produce lui'gi*r crojis, 

 due to the accumulation within the soil of suitable i)lant-iuod derived 

 fi'om the manure, wliich may be reduced or entirely withdrawn by the 

 crops. But since it is the minimum of any one essential ingredient and 

 not the maximum of the others which is the measure of fertility, a soil 

 may become exhausted for one plant yet still contain an abundant food- 

 supply for another plant whose food requirements are different. Thus 

 a rotation of crops will defer the period of exhaustion. A poor soil is 

 sooner reduced to sterility than a rich one, a shallow soil would fail 

 sooner than a deep one, and a light soil sooner than a stiff one. As 

 only about 1 per cent, of a soil is in a fit condition at any moment for 

 plant-food, an immense store of nourishment is contained in most soils 

 in a passive condition, which gradually becomes available. 



IMPROVEMENT OF THE SOIL. 



The improvement of the soil by tillage, drainage, irrigation, liming, 

 and the application of manures does not enter into the subject of this 

 report, and the reader in quest of such information is referred to any of 

 the standard works on agriculture, where these subjects are treated in 

 full detail. 



THE MECHANICAL ANALYSIS OP SOIL. 



At one time great stress was laid upon the mechanical analysis of a 

 soil, and chemists were told that more depended on it than on the 

 chemical composition, but nowadays, whilst a knowledge of its phys- 

 ical condition is a great help in studying the nature of a soil, still its 

 chemical analysis is of more importance. 



Of the great number of apparatus proposed to effect the mechanical 

 analysis of soils, all labor under more or less objections, and the same 

 soil submitted to difi'erent processes yields most diverse results. 



An Italian chemist, M. Pellegrini, obtained the following results 

 with a clay soil of Orciano, near Pisa, on using the apparatus named 

 (Peligot, Trait6 de Chimie Analytique appliqu6e a L'Agriculture, 1883, 

 p. 154) : 



Noeble's. ■ 



Scliloes- 

 ing'a. 



Masure's. 



Sand 



Clay 



Earthy carbonates 



Orj^nuic and volatile matter. 



Undetermined.' 



Soluble and loss 



1.47 

 87.31 



L56 

 100. 00 



32.07 

 37.67 

 20.20 

 10.25 



100. 19 



13.35 

 71.90 



14.75 



100.00 



