468 TRANSACTIONS OF THE 



the soil, being unstirred for about half a year, becomes close paclced, and 

 does not admit of seed sinking into it, of young plants spreading out their 

 roots, nor of water and air permeating it, and giving nutriment and mois- 

 ture to the plants. There are also seeds, either in growth or in the germ, 

 which, if allowed, would overpower the young crop, and appropriate to 

 themselves the pabulum furnished by the soil or by manures. To fit such 

 ground for the reception of seed — to loosen it — to pulverize it so that seed 

 may sink into it and take root — to render it permeable to air and water, so 

 that the mineral constituents of the soil may be acted upon by these, and 

 may absorb and fix volatile agents from the atmosphere to become food for 

 plants — to invert weeds so that, being placed in a position contrary to their 

 natural growth, they may die — to level the surface, or to form it into beds 

 or hills, as may be required — all these must be done by an apparatus worked 

 by steam, in order to completely solve the problem ; and, moreover, they 

 must be done at least as cheaply, as easily, and as effectually, as they are 

 done now by annimal power. If any apparatus, claiming to have solved 

 the problem, does not fulfil these conditions, its success, however great, is 

 only partial, and there is still room for a valuable invention. 



There are three kinds of engines — the locomotive, the portable, and the 

 stationary — capable of- being employed in steam cultivation; and there 

 may, consequently, be three kinds of steam cultivation invented, each 

 characterized, in its general features, by the kind of engine employed ; 

 though under each class there may be many modifications of parts, render- 

 ing the members of the same class as widely different as those of different 

 classes. These varieties would be determined by the structure, form, or 

 size of the engine itself — by the mode of conveying the power to the tools 

 or implements with which it works — and by the nature of the tools or im- 

 plements it uses. 



The locomotive engine may be employed merely for traction, to draw 

 plows or other implements after it ; or it may be employed both to move 

 itself over the ground and to work some form of revolving cultivator, or 

 some form of spading apparatus, &c. A great objection to the use of the 

 locomotive is its great weight, which is injurious in several respects. The 

 moving of so great a weight from place to place consumes a very large per- 

 centage of the power ; so great a weight cannot be supported upon narrow 

 wheels on soft ground, for it would sink them into the ground, and render 

 locomotion impossible ; so gi'eat a weight upon broad wheels rolls and com- 

 presses the ground, permanently hardening the subsoil, and increasing the 

 work of turning or pulverizing it ; also, the jolting and jars which a heavy 

 engine moving over irregular ground receives, must seriously injure, and, 

 in a short time, destroy it. Another serious objection to the use of a loco- 

 motive is the difficulty of getting it to move up and down grade with ease 

 — a difiiculty that has not yet been overcome satisfactorily upon well-made 

 roads, and one that is not likely to be easily overcome upon irregular 

 ground. The locomotive engine, also, when working by traction on moist 

 ground, is liable to slip — to have its wheels turn without its moving forward. 



