108 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 8 



it is the object of the writers at this time to present the general arrange- 

 ment of the apparatus, the principle of operation, and the moisture 

 and temperature records maintained in the breeding chamber. 



The spray chamber shown at A (Plate 1) is nine feet long and is 

 provided with nozzle standpipes B, arranged in two groups or banks, 

 placed about three feet apart, with the last bank three feet from the 

 ehminator plates. The flooding of the eliminators is done by an inde- 

 pendent set of nozzles shown at C across the top. These nozzles dis- 

 tribute the water over the washing surface uniformly. Valves shown 

 at D outside of the spray chamber are provided on each bank of nozzles 

 and also on the flooding nozzles over the washing surface, and thus 

 either or both banks of nozzles can be closed to regulate the humidity. 

 With both banks of nozzles closed, no appreciable increase in humidity 

 of the air is produced. With one bank in operation (and the water 

 recirculated w^ithout being heated) the humidity of the air will be 

 increased about sixt}^ per cent. With both banks of nozzles in opera- 

 tion, the humidity is increased about eighty per cent. If the water 

 is heated the air leaves saturated. The banks of spraj^s can be opened 

 or closed and the temperature of the water also varied as required. 



Two water-tight inspection doors shown at E (Plate 1) are pro- 

 vided to allow easy access to the spray chamber. Beneath the entire 

 washer and eliminator is a settling tank F, sixteen inches in height. 

 A strong frame, built of angle iron, encloses the settling tank, to w^hich 

 it is firmly united, making a very rigid and substantial base to support 

 the balance of the washer. The tank is provided w^ith an automatic 

 float valve, which controls the water supply and maintains a constant 

 water level in the tank; an overflow valve G, which connects to the 

 sewer and which prevents flooding the tank; a drain valve arranged 

 under the bottom of the tank and which connects to the sewer, so all 

 the water may be drawn off for cleaning. 



The settling tank is divided into two compartments by a wire cloth 

 strainer, through which the water passes before entering the suction 

 of the pump H. 



Connected to the passage just be3^ond the eliminator chamber is the 

 air suction fan shown at K (Plate 1) propelled by a steam turbine L. 

 This fan draws the air through the spraj^ chamber of the air washer 

 and humidifier, w^here it comes in contact with the atomized spray of 

 water. The evaporation of a portion of the spray water humidifies 

 the air and the amount thus evaporated depends upon the relative 

 temperature of the water. Leaving the spray chamber, the air next 

 passes over the washing surfaces of the eliminators and then over the 

 stem of a graduated thermostat shown at M (Plate 1) placed in the 

 passage just beyond the eliminators, so that it is exposed to the tem- 



