Another form of the same class of lever-harrows is shown in Fig. 6, and is strongly made of pipe passing loosely through transverse flat girts, each piece of pipe being connected by an arm pivoted to a horizontal bar, in turn pivoted to the hand lever for adjusting the pitch of the teeth. A lever-harrow by the Ray Implement Co., shown in Fig. 7, has a bearing shoe at the corner of each section. In transporting this harrow, when it is not desired to operate it, the teeth are thrown hack horizontally by the lever, and the corner shoes take the ground as runners. The H. P. Denseher Co. makes a harrow with sledge runners so arranged as to carry the implement folded and reversed when transporting it not in use. The class of harrows represented by the Kalamazoo spring tooth harrow (Fig, 8) is not only adapted by the yielding teeth to land that is obstructed by earth-fast stones and other objects, but, owing to the vibratory action of the helix spring-teeth, pulverizes the soil thoroughly, shakes it up and leaves the dirt in a loose condition, shaking out weeds and grass upon the surface, leaving them exposed to the sun to wilt and die. In operation the flattened frame pieces hold down the sods and clods, while the teeth cut deeply through instead of rolling them up. Each tooth has a bead punched up near the heel, which matches a east-iron socket on the harrow frame. The socket is made with a rib which matches a slot in the harrow frame, and has side flanges to prevent the tooth from swinging to either side. The tooth is held to the socket by a steel clip. The same class of harrow is sometimes iron plated on the bottom surface of the frame to promote durability, and sometimes made with the frame entirely of iron or steel, corrugated longitudinally to render it rigid. The teeth are
also sometimes made with the heel prolonged and continuing the normal curve, so that as the points wear away the depth of cut can be maintained, and the service of the teeth in creased by changing the point of attach ment nearer to the extremity of the heel as occasion may require. Fig. 0 is the Hoosier pressure-harrow, with a band lever attached to a rock-shaft hav ing a series of arms controlling the depth of cut by means of connecting rods. The teeth are fitted with springs at the heels, permitting them to yield to avoid break age. By removing or folding up the middle tooth, the harrow is used as a corn cultivator, the dragbar support being high enough to pass over the grow ing corn. Fig. 10 exhibits the Heneh & Dromgold method of securing the fiat class of spring-tooth on a steel-frame harrow. The tooth is riveted to a malle able iron hub with ratcheted sides, and a bolt passes through the frame pieces of the harrow, and two circular plates with crown ratchets to engage the hub ratchets As the tooth wears away and shortens at the point, the hubs may be correspondingly rotated by loosening the bolt and then retightening it, to maintain the normal depth of cut, so RE greatly to increase the service of the teeth before exhausting all their available spring action. The grubber (Fig. 11) is distinguished by a pair of side carrier-wheels and a lead-wheel.
These wheels merely limit the depth of cut by the teeth as long as the hand lever is latched back; hut when the lever is released, the advance of the teeth lifts the teeth from the ground, and loads the machine bodily upon the wheels.