470 BOARD OF AGRICULTURE. [Pub. Doc. 



built a small machine shop, and, with the assistance of Mr. John 

 Hancock, a skilled machinist, the invention and manufacture of 

 nozzles, hose, couplings, poles, pumps, tanks and trucks, for use 

 in the field work of the Board, was begun. Several different 

 machines were made and used in the field, but the one which is 

 herein described has given the best service, and is considered a 

 distinct improvement over anything yet made for the purpose. 

 Much time and thought have been given to the study of steam or 

 gasolene engines for spraying; but the use of these engines. was 

 finally abandoned, as the pump alone is less complicated, and 

 consequently less likely to break down and thereby cause delay in 

 the field. 



The Pump. 



The pump (shown on Plate X, Fig. 5) is built somewhat on the 

 principle of that used in the hand fire engine, but is worked by 

 one man, with a detachable lever (m) in place of the brake. All 

 the working parts are made of brass or composition, to resist the 

 corrosive action of the arsenate of lead. The volume of water 

 thrown is small, but with a small outlay of power a pressure of 

 eighty to one hundred pounds to the square inch can be had, this 

 being all that is oi'dinarily required to get the best results in 

 spraying. The pump is placed inside the tank, and when the 

 tank is full is under water ; the machine is thus compact, and a 

 number of connections and devices, usually required where the 

 pump is outside the tank, are done away with. The pump is so 

 constructed that no stuffing boxes are necessary ; this does away 

 with all packing, and saves the time so often lost in repacking. 

 There is an agitator attachment, consisting of two sheet-iron 

 plates (Plate X, Fig. 5jp). These are fastened to the cross-beam, 

 and by it are worked alternately up and down through the liquid 

 so long as pumping is continued. This keeps the liquid agitated, 

 and for this purpose the pump should be kept working continually. 

 When the pressure reaches eighty to one hundred pounds, the 

 relief valve (n) comes into play, and the water which is released 

 from the valve flows back into the tank. If spraying is not in 

 progress and the water is shut off from the nozzles, the relief 

 valve, by preventing a higher pressure, saves the hose. From 

 one to three nozzles, containing four outlets each, can be run at 

 this pressure by one of these pumps. To prevent a clogging of 

 the machine by foreign material, the holes which are drilled in the 

 suction pipe are covered with a fine brass wire screen, the meshes 

 of which are finer than the outlet of the nozzle. On the upper 

 surface of each of the agitators there is fixed a cylindrical iron 



