BARREL AND TANK SPRAY-PUMPS. 277 



with an air-chamber surrounding the cylinder." Thus, although the 

 outside casing of the air-chamber may become accidentally bent, that 

 of the cylinder within is protected against such injuries. Also this 

 construction gives such pumps a more compact form, rendering them 

 simpler and stronger. The pump is shown in section in Plate XLII, 

 Fig. 2, where h is the handle, b the solid piston in the cylinder with a 

 guide-cap. c, at its top, iucurrent valve below, and excurrent valve, i, 

 to the air-chamber, e, which surrounds the cylinder as shown. A stiff 

 discharge-tube, a, penetrates this chamber from its top to near its base, 

 while its upper part has a horizontal tube, m, from the cylinder, as an air- 

 vent, which also communicates with an overflow-pipe, n^ extending down- 

 ward on the outside of the air-chamber. In cheap pumps made of thin 

 sheet-metal this protection of the working cylinder by an air-chamber 

 encasement is certainly a very good plan. Tlie air-chamber may fit as 

 though it were a bung in a large hole through a fixed or removable 

 head or septum of the vessel, and attachment by a flange or otherwise 

 is easily contrived. 



The Helmecke Spray-pump is of the same desciii^tion with slight mod- 

 ifications consisting chiefly in placing a lever upon the piston, and the 

 overflow-pipe inside of the air-chamber as patented in l^o. 206448, July 

 30, 1878, by Mr. F. A. Helmecke, of Eound Top, Fayette County, Texas. 

 This pump is illustrated in longitudinal section in Plate XLII, Fig 1. 

 The lever, c, is linked (x) to a i)ivot above the discharge spout and works 

 the plunger, &, in the cylinder, a. Below is a suction-strainer and valve, 

 V 0. Higher is an outlet valve, d, to the air-chamber, e, and discharge- 

 spout, /j, while much higher is the overflow-pipe, ej\ extending down 

 through the air-chamber. Being entirely round on its outer surface 

 the pump is readily inserted in a large bung-hole of the barrel or poison- 

 receptacle and is thus held while beiug worked. 



A i^ump having its cylinder protected by an air-jacket was also made 

 and used in Fayette County, Texas, at about the same date as the lat- 

 ter in an apparatus which has been thus described by Professor Eiley: 



"The Yeager Sprinkler. — This is a sprinkler inrented by Mr. George Yeager, of 

 Flatonia, Tex., (patent No. 204410, May 28, 1878). Plate HV, Fig. 6, is a part sec- 

 tional side view, and Fig. 7 a plain view thereof. 



"■ It consists of a platform, A, upon which is laid a barrel, B, containing the poisonous 

 liquid. A rubber hose, C, connects this barrel with the bottom of a pump cylinder, 

 D. This cylinder is supported on a step, A^, and its upper end held in a brace, A'-^, 

 attached to a standard, A^, which rises from the platform, A. E is the pump-plunger, 

 connected to a lever, F, which is x^ivoted in the upper end of the standard, A^. The 

 liquid poison is forced out through the sprinklers, G G G, which are three in number, 

 and throw the water in a fine mist over three rows of cotton. A rubber hose, I, is 

 attached to each of the sxiouts, H, of the pump to form counection with the spriuklcrs 

 G for the purpose of lengthening or shortening the spouts, especially the two on op- 

 posite sides of the pump, and of detaching and cleaning the sprinklers. The upper 

 end of the pumpt-cylinder is left open and a spout or tube, J, is connected thereto to 

 conduct the liquid, which would otherwise be wasted, back into the barrel. 



"The connection of this waste-pipe with this machine is the only point which is 



