Fig. 9 shows the Jacob Price plowing outfit, his plowing engine drawing four gangs of three plows each at the California State Fair of 1890. made by J. I. Case, of Racine, Wis.: weight of engine, 8 tons, the twelve plows cutting 11 ft. wide. The four gangs are independ ently attached to a strong, light platform running on casters, and the lifting lever of each gang is so arranged that the fireman can handle it from the run-board of the platform with out descending to the ground, while going. The platform is hooked to the engine at only one point, and the whole rig is designed for lightness and strength. distributing the strains. In this class of steam-plowing the running speed is from 21 to 41- miles an hour, according to the character of the soil and the number of plows drawn. The bearing surfaces of the three engine wheels are extraordinarily broad in proportion to the weight of the engine, and pre vent sinking into the face of the ground even on soft land. On ordinary soft prairie or ure land they leave but a faint impression. The two tlriving-wheels are 8 ft. high, with 26 in. of face. Large, wide wheels allow the use of numerous grouters or lugs of moderate pro jection, an advantage when the ground is hard and impenetrable, instead of the few but very prominent grouters requisite on the smaller traction wheels of farm engines of ordinary type.
To lighten the engine, a high-pressure boiler with thick walls is used under heavy steam pres sure, increasing power relatively to weight of engine and boiler as a whole. and yielding a large power available for draft in excess of the power consumed by the engine in propelling itself. Fig. 10 is a side view of the latest model of the Jacob Price held locomotive, specially designed for plowing, though available for other mobile or stationary work. It is estimated at TO horsepower. It performs the duty of forty actual horses in pulling, besides its self propulsion. Driving-wheels 8 ft. x 28 in.; steering-wheel 5 ft. x14 in.; capacity of water
tank 500 gallons: of fuel-boxes 1.500 lbs. of coal. The boiler is a combination of the upright and horizontal types, with a working pressure of 150 lbs. per sq. in.. driving twin engines having piston valves. It consumes about 250 lbs. of coat per hour. Wood may be used for fuel if desired It has two speeds, the plowing speed of about 3 miles, and travelling speed of 5 miles per hour. Fig. 11 illustrates Deere's arrangement of steam-operated plows with an ordinary farm traction engine, drawing a gang of five plows; duty, acres of land per hour with engine geared to make a speed of 2 miles per hour, cutting 14-in. furrows; or 11, acres of land per hour if cutting 12-in, furrows. If the steering wheel of the engine is upon the right-hand side, right-hand plows are requisite (and vice versa), to give the operator an unob structed view of the work and enable him to preserve a uniform land. When once set, the plows require no attention for depth and land, but are thrown out and in by one lever at the ends of furrows. The outfit requires two attendants, besides a boy and team to supply fuel and water. The land should be fairly free from obstructions and in condition for plowing. Of this subject it may be stated that steam-plowing has passed the experimental stage in the United States, but is still in its early period of application. Economy and practicability are demonstrated. The introduction, though a fact, is not yet very general; but it is a mere question of time when the plowing of large areas will be done generally by power other than Phig,-and-Feather Process : see Quarrying Machinery.
Pneumatic Dredge : see Dredges and Excavators. Gun : see Gun, Pneumatic. Ham mer : see Hammers, Power. Stacjier : see Threshing Machines.
Polishing. see Sash Machines, Sand-papering Machines, and Wheel-making Machines.