Page:Encyclopædia Britannica, Ninth Edition, v. 1.djvu/339

Rh IMPLEMENTS.] AGRICULTURE 313 The Dude or Uley cultivator has many features in common with Biddle s, and although brought forward as an improvement upon it, has not established its title to be so regarded. The great weight, high price, and amount of horse-power required to work them, are serious objec tions to all these implements. Of more recent notoriety than these, and contrasting with them favourably in these respects, is an implement invented by the late Mr John Tennant, at Shields, near Ayr, and now popularly known as Tennant s grubber. Its construction, as the annexed cut will show, is simple in the extreme. Its weight is about two cwt., its price 4, 10s., Tennant s Grubber, as improved by T. Brown, Edington. and its draught easily overcome by two horses. The depth at which it works is regulated by raising or lowering the shank which supports its wheels in front. Its tines can be easily moved on their supporting bars, and it may be worked with five or seven as desired. By substituting a shorter hind bar. and setting the tines more closely to gether, it makes a most efficient drill-grubber. We shall have occasion to refer to this implement frequently in treating of tillage operations. The improvement which. Mr T. Brown has made on Tennant s grubber consists mainly in the mode of attaching the tines to the bars. This attachment, which the cut explains, has the merit of being at once very simple and very effectual. The tines when thus fixed are as rigid as if welded to the bars, and yet, by merely slackening the screws and driving out the wedges, they can with ease and rapidity be either adjusted at varying widths apart,, or detached for repair. A, Tine ; B, Keeper ; C, Wedge. Actual Size. Section 4. Steam-Power Tillage Implements. Such are the most important of those implements by which the tilling of the soil has hitherto been accomplished, and upon which the farmer must continue to rely so long as he uses the muscular force of animals as his motive power. Fowler s Locomotive En But the progress of invention has at last made the steam- engine practically available for this purpose, and accordingly we here introduce some notice of what has now been accom plished, in applying steam power to the cultivation of the soil. After many abortive attempts to do this by moving the engine itself over the land to be operated upon, it is now admitted on all hands thnt the only available method is to gine, with Clip Drum. communicate the power from the engine to the implements by means of steel wire-ropes and windlasses. This is done in a variety of ways, some of the most prominent of which we shall now describe. The systems actually in operation fall under tw general classes, which are known severally as the &quot; Direct&quot; and the &quot; Roundabout.&quot; The first of these is the system introduced by Messrs John Fowler & Co. of Cornhill, London, and now so well known in connection with T. 40