5 CIRCULAR 457, U. S. DEPT. OF AGRICULTURE 



The apparatus consists of a rectangular box 2 feet square and 3 feet 

 long, of 18-gage galvanized sheet iron on a frame of li/^-inch angle 

 iron. At each end is a cone 18 inches long, terminating in an open 

 pipe, the intake pipe being 5 inches and the outlet pipe 6 inches in 

 diameter. Within the box, sliding upon supports of lV^-inch angle 

 iron riveted to the frame, are three trays, each 23 by 34% by 2 inches, 

 and each capable of holding about 15 pounds of sulphur. The sides 

 of the trays are strengthened by pieces of 1%-incli strap iron, and 

 a piece of the same material is run from these crosswise beneath the 

 center of each pan to prevent sagging. The door at the side is se- 

 cured by bolts and wing nuts. To prevent the gas from escaping, a 

 gasket of .asbestos cloth is placed between the door and the body of 

 the burner. All seams and connections are strongly crimped or 

 riveted, as the heat of the burning sulphur will quickly melt any 

 solder work. 



Figure 2. — Diagram showing details of construction of the sulphur burner. 



In preliminary tests it was found that the sulphur in the middle 

 tray burned faster than that in the top and bottom trays, owing 

 to uneven distribution of air. This condition was corrected by baffles 

 in the intake funnel. The baffles are of 18-gage galvanized sheet iron 

 cut to fit the intake cone, with a piece of three thirty-seconds by 1%- 

 inch strap iron riveted to the center of each, longitudinally. The 

 ends of the strap iron are pierced with holes and project into the 

 intake pipe, being held in place by bolts, the nuts of which are 

 outside, on top of the intake pipe (fig. 2), to allow adjustment of the 

 baffles. The bases of the baffles rest upon the tray supports. The 

 spacing of the baffles must be determined by testing, or by the use 

 of an anemometer, so that each pan receives air at the same rate. 



The fan used is of the centrifugal type in a steel housing, con- 

 nected directly to a one-twentieth horsepower electric motor running 

 at 1,750 revolutions per minute, and with a horizontal 5-inch dis- 

 charge and 6-inch single suction. This fan deHvers 150 cubic feet 

 of air per minute. Since the outlet from the burner is an inch 

 greater in diameter than the intake, there is practically free delivery 

 of air. In use, the fan is connected to the intake, and stovepipe 

 is led from the delivery pipe into the house through an asbestos- 

 lined opening in a false door made of wallboard. It is advisable 

 to extend the outlet, by means of several extra lengths of stove- 

 pipe, so that the delivery of gas will be along the floor in the cen- 



