Application of Steam Poicer to Cultivation of the Land. 175 
by degrees in the field. Accordingly, the " heads " specified 
for the present paper embrace — first, " a general description of 
the methods now in use, and of such success as has been 
attained and, second, " a detailed account of one or more cases 
where steam power has been employed in the ordinary cultiva- 
tion of a farm. ' 
The " methods now in use," and, indeed, all forms of steam- 
cultivating apparatus, are based upon two distinct principles, and 
may, therefore, be classified thus: — Steam ma.c\\\nexy drag r/ing 
" traction implements," and steam machinery tillinr/ tlte ground hy 
otlier means. And then, as an accessory to the primary purpose 
of tillage, or the mechanical preparation and treatment of the 
soil, we have the locomotion of .'steam-engines in fields and upon 
common roads. Incidental to the subject, there are also the 
manipulation of crops in the field, weeding, manuring, dressing, 
&c. ; but all these are subsidiary to the main operation of 
" tillage." 
I will first devote some little space to the consideration of 
Machijtery Acting Independently of Traction. 
Although the application of steam power to the hauling of 
implements has been eminently successful (as will fully appear 
in the course of this paper), producing a better description of 
work, operating at less cost, and enabling the condensation of 
preparatory tillage into suitable moments to a greater extent 
than could be attained by any amount of horse-labour, still there 
are those among us who look for a yet greater economy and a more 
garden-like process of culture when steam is set to grapple with 
the soil in its own way, instead of being merely substituted for 
horses in doing horses' imperfect work. I shall not quote the 
conclusive teachings of the " Clay-farm Chronicler " on this 
point, but simply endeavour to point out the promised and 
partially-realised advantages of the rotary tillage he advocates. 
And I am happy to say that none of those multitudinous inven- 
tions are at present before the public which aim at imitating the 
action of spades, mattocks, or other hand-tools, by means of 
arms, cranks, eccentrics, joints, slides, and levers, — a complicated 
mass of moving parts foreign to the portability and simple utility 
of a farmer's field machinery. We have only machines for cul- 
tivating by the continuous circular motion of a shaft or cylinder, 
armed with shares or cutters, driven more or less directly by 
the engine. Now, the operation of tillage consists in thrusting 
into or passing a wedge through the soil, and then lifting (or 
not) the separated portion ; no matter whether the wedge has a 
horizontal rectilinear motion, as a ploughshare or grubber-tine, 
