4 BULLETIN 1375. IT. S. DEPARTMENT OF AGRICULTURE 
Figures 1 and 2 show testers equipped with burners for using gas 
as fuel. The form of construction, however, is such that alcohol 
or gasoline burners, or electric heaters can be used, provided the di- 
rections herein given are carefully followed. 
CONSTRUCTION SPECIFICATIONS 
The heating chamber is 3 feet 2y 2 inches long, and is divided 
into six compartments, each 5y 2 inches square and Qy 2 inches deep, 
inside measurements. The compartments are separated" by air spaces 
one-half inch wide. Each compartment is lined with T 3 F -inch asbestos 
sheeting (transite board). 
The heating chamber is made of heavy, galvanized iron through- 
out. The sides extend 7y 2 inches below the chamber on the back and 
the two ends to form a stand, and are rolled at the bottom for firm 
footing. The front side extends only iy 2 inches below the chamber, 
and to this side is attached a rack l 1 /^ inches wide extending the full 
length of the chamber which is provided with holes for holding 
thermometers when not in use. The heating chamber has a hole 3 
inches in diameter cut in each end, in line with the burners. (See 
%. i.) 
A galvanized angle iron seven-eighths inch wide is riveted around 
the inside of each compartment as a rest for the wire gauze used 
over the gas flame, on which the flask seat is placed. Each compart- 
ment has a 2 ^-inch round mica window for observation during 
test. 
Each compartment is provided with an asbestos-lined (transite 
board ) cover with a 1^-inch opening in center to allow for pro- 
jection of neck of flask when closed. 
Each compartment has a cut in back five-eighths to three-fourths 
inch wide and seven-eighths inch deep on center line of compart- 
ment, to allow for projection of stem of flask which leads to con- 
denser tank. 
A copper condenser tank 4 inches wide and 12 inches deep extends 
the full length of the heating chamber. This is mounted on the 
base back of the chamber. 
The tank has a ^-inch inlet pipe at the bottom and a %-inch over- 
flow pipe three-fourths inch from the top. The tank has six open- 
ings in the bottom so arranged as to coincide with the center line of 
the compartments for condenser tubes: these openings are large 
enough to take a Xo. 5 rubber stopper and are reinforced by a cop- 
per plate iy 2 inches in diameter sweat to the bottom. 
The base for the heating chamber and condenser tank is 3 feet 
3% inches long, II14 inches wide, and IIV2 inches high. The legs 
are made of 2y 2 by 2y 2 by y 8 inch angle iron and tied across back 
and ends by 1 by 1 by y 8 inch angle iron. Tie angles are mitered at 
comers and set inside of legs to form seat for chamber and tank. 
The end legs are tied 2y 2 inches from bottom by a % by % by y$ 
inch angle iron. From this angle to top angle, two 14-inch round 
rods are set iy± inches apart center to center, between which the 
gas line pipe is passed and a lock or clamp nut is placed on pipe on 
either side of rods for clamping pipe into position, making same 
adjustable up and down. 
