116 FUMIGATION METHODS 
thrown up beneath the hood the shelf is tipped and 
the cyanide dumped into the generator. This device 
is simple and cheap. 
A good Western idea.—A Western firm has a 
novel and practical way of making an open floor and 
generating the gas underneath. They say: ‘‘Our 
fumigating house is 15x 20x10 feet. The walls are 
double, of one-inch plank, the first course being put 
ou lengthways of building, then common building 
paper, tarred after being put on. ‘The second course 
of plank is put on up and down. This course is on 
the outside; roof made the same way; doors simi- 
larly made, are double, and take up one end of the 
building. After the building was completed, we 
banked up around the bottom about a foot with dirt ; 
then we excavated about a foot and a half deep, one 
foot from the bottom of the walls. For instance, if 
the room was 10x 20 feet, the excavation would be 
g x 19 feet, surface measure. Over this excavation is 
laid three 2x4 inch joists, just enough to hold the 
stock which is put in for fumigating. Across these ' 
joists lay two or three 12-inch planks, loose. ‘This 
completes the house. 
‘‘An opening or flume is made under the wall about 
one foot deep and eighteen inches wide. The end 
extending into the inside of the building is open, and 
extends just far enough to let the gas into the exca- 
vation under the trees. The outer end extends out 
far enough to give the operator ample room to insert 
the vessel containing the chemicals. The outer aper- 
ture is covered with a trap-door. ‘The vessel with the 
acid and water is set in the flume, trap-door open, and 
