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Tf small seeds are sown on such a rough surface, they are liable to 

 suffer for lack of moisture. It is customary, therefore, and very advis- 

 able in such cases, to harrow and roll the seed bed until all tbe larger 

 lumps are broken down and the surface is left smooth and even, in 

 order to insure a supply of moisture to the seed during the germinating 

 period. However, soil which has thus been rolled will lose more water 

 by evaporation than soil which has been simply harrowed. The evapo- 

 ration of this moisture is an incident which it is not always possible 

 or desirable to prevent With some crops the surface may be har- 

 rowed after the seed has germinated. This is desirable when it can be 

 done without injury to the crop, as it tends to retard evaporation. 



There is one serious defect in the principle of the common plough 

 which, upon some soils and with certain kinds of ploughing, is liable to 

 have very serious effects. If a field is ploughed for many successive 

 years to a depth of 6 or 8 inches the tendency each time is to com- 

 pact the subsoil immediately below the plough, thus rendering it more 

 impervious to water; that is, the plough in being dragged along plasters 

 the subsoil just as a mason with his trowel would smooth out a layer 

 of cement to make it as close and impervous to water as possible. 

 This is undoubtedly an advantage to some soils, but, on the other 

 hand, it is very injurious to many. 



The injurious effect of this compact layer formed by the ploughing is 

 twofold. It makes it more difficult for the rainfall to be absorbed as 

 rapidly as it falls, and increases the danger of loss of water and injury 

 to the soil by surface washing. Soils ploughed at a depth of 3 or 4 

 inches, which is quite common in many parts of the country, would 

 have a thin layei of loose material on the surface, with a compact 

 subsoil below, into which water would descend rather slowly. With 

 a rapid and excessive fall of rain, the light, loose topsoil is liable to 

 be washed away by the excess of water, which can not descend into 

 the subsoil as rapidly as it falls. This washing of the surface and 

 erosion of fields i to gullies occasion the abandonment of thousands 

 of acres of land. The &Ad will not wash so badly if it is not ploughed, 

 and, on the other hand, it will hardly wash at all if the cultivation is 

 deeper and the subsoil left in a loose and absorbent condition. The 

 deeper the cultivation, the greater the proportion of rainfall stored 

 away and the less danger of the erosion of the surface soil and the 

 less serious the defect of our common method of ploughing. While 

 there is less danger from washing, however, with deep cultivation, 

 there is still a tendency towards the formation of a hardpan at what- 

 ever depth the land is ploughed. No simple modification of the ordi- 

 nary plough or of the subsoil plough will overcome this defect. It will 

 require a change in the very principle of the implement. The plough 

 should not cut through the soil, but break it apart so as neither to 

 compact nor puddle it by being dragged along over the subsoil. 



While all other farm implements and machinery have been im- 

 proved, especially within the last fifty years, so that we are able 

 now to harvest more crops than ever before and to handle our 

 crops to better advantage, our common plough has not been essen- 

 tially improved or modified in any important particular, except as 

 to mechanical construction, since the da\sof the early Greeks and 

 Romans. It would seem only necessary to call attention to this, the 



