Fig. 11. represents another kind of a cutter circle, which probably might have been found on trial pre ferable to the one that was introduced into the machine; the cutting part of it was to have been made in seg ments of iron faced with steel of a shape that would have admitted the whole length of their faces being struck or cut with teeth, at a proper angle, similar to those of a coarse struck reaping hook : the form of these segments are represented in the Fig. at x x x, Scc• there were small tongues t t t, &c. to be formed on the cast iron part of the cutter circle of the same height with the thickness of the cutter segments, and which, with the screws shown in the figure, would have effec tually prevented the segments being forced out of their places : the front prongs shown in this figure are to be supposed as those of the under frame, and which arc there placed to show the form that they ought to have been made of, so that this circular cutter might have cut to the best possible advantage against each prong. The bottom prongs are there represented as covered with those of the rolled iron plate circle, as described by the other figures, and which in Fig. 11. is to be sup posed to extend to the dotted circle a b c d, as in Figs. 3. and 5.
All the figures are drawn to a scale of twenty inches to the inch, except Fig. 12. which is drawn on a larger scale, on purpose the better to show how the collectors Fig. 3. arc wrought. In Fig. 12. tyat represents part of the drum, and a b c de part of the hoop that works the tails of the collectors ; s and a represent two of the eyed studs that are fixed into the upper and under hoops that strengthen the drum, for the pivots of the axes of the collectors to play in. t and t two of the longer studs fixed in the underhoop of the drum, for the hing ed tails x and z to play in. The tail z is represented as moving in its groove, and the tail v travelling in its slit, and which is just about being directed into its groove by the curved piece d, when at the same time the tail z will enter its slit, and the hook of the collec tor in will be thrown into a position similar to that of n. And again the tail u is represented as moving in its groove, and the tail a- in its slit, and which is about be ing guided into its groove by the curved piece b ; when at the same time the tail u will enter its slit, and the hook of the collector n will be thrown into the position of at in the figure. Y Fig. 12. represents one of several thin brushes fixed into the under rim of the drum, made of two pieces of iron rivetted together, with a range of bristles between, for sweeping forward the root end of the cut corn, and keeping that part of the cover plate clean swept.
The reaping machine here described differs much from all those attempts that the writer of this article had any knowledge of, not only in the construction of its different parts, but also in the nature and form of its cutters and front prongs, as likewise in the method of working the machine itself.
With regard to the cutters, a variety of experiments were made with cutters of different forms, as also in the manner of applying them, when it was ascertained that the draw cut of a common reaping, hook was in ferior to none for cutting corn, besides having the pro perty of seldom requiring sharpening, as is manifest from the common reaping hook, that will cut for a whole harvest without requiring sharpening. But to give toothed cutters that are fixed upon a revolvino. circle, the best form to act similar to a draw cut, it is necessary that they form an angle of forty-five degrees with the diameter of the revolving circle on which they are fixed ; but from the variety of positions that cutters moving circularly present themselves to the corn dur ing every. .revolution, no two of them can cut the corn to the same advantage, if the straight prongs that have been adopted by others were to be used; it was fore found absolutely necessary to form that part of the front prongs against which the cutters cut the corn, in lines that formed with the cutters the angle of forty five degrees, as represented in the figures.
With regard to working the machine ; the difficulty in working a reaping machine arises from the corn that is to be cut standing in the way of the best possible line of draught, and the necessity of yoking the horse in such a manner that he shall neither tread upon the cut or uncut corn. Trials were made on different me thods, but the one that was found to be by far the most suitable, was nearly upon the principle that boats on canals are drawn by horses ; the boat is kept in the middle of the canal by means of the helm, the horse is yoked to the boat by means of long traces, and walks at the distance of between three and four feet from the brink of the canal. To apply similar principles to a reaping machine, handles of sufficient length were placed behind the machine, to give a man power to keep the roller wheels upon which the machine moves at right angles to the line of the corn to be cut, so as to produce an effect similar to that of the helm upon the boat.
The horse was yoked with traces to the fore corner of the machine next to the stubble, as shown by Fig. 3, where he was at liberty to travel without treading either upon the cut or uncut corn, and exactly in a line paral lel to the direct course of that point of the machine to which he was yoked, and not, as in the case of the canal boat, at several feet distance from the parallel of that line, which shows that a horse can be yoked in a more advantageous line of draught to a reaping machine than to that of a canal boat ; besides, the left hand roller wheel on the side that the horse draws the machine, works all the machinery part, and therefore makes it no way dif ficult for the man at the handles to keep forward the right hand roller wheel, it. being at liberty to turn freely upon its axis.