144 FUMIGATION METHODS 



house is determined in the same manner, except that 

 the two triangles being unequal, each one will have to 

 be calculated separately. The house contains 15,050 

 cubic feet. It will thus be seen that the cubic con- 

 tents of a house or frame of any style can be readily 

 determined by simply dividing a cross-section of the 

 same into the necessary number of triangles and reel- 

 angles, and calculating as demonstrated above. 



Cold frames. That cold frames can be successfully 

 fumigated has been shown by recent practical work. 

 Make the frames as nearly air-tight as possible, and 

 cover them with blankets or canvas if necessary. 

 Kstimate the cubic contents of air space inclosed, and 

 then calculate the amount of cyanide necessary. For 

 example, suppose a frame contained 567 cubic feet. 

 Multiply this by 0.15, an equivalent of 0.15 gramme 

 cyanide per cubic foot. Therefore, 567 x 0.15, equals 

 85.05 grammes; reduced to ounces by dividing by 

 28.35, as there are 28.35 grammes in an ounce, gives 

 (85.05 divided by 28.35) 3 ounces the amount of cya- 

 nide required. 



This inclosure would require 3 ounces cyanide, 4^ 

 ounces sulphuric acid and 6^ ounces of water. After 

 the cyanide is determined it is easy to estimate the 

 acid and water. Use a half more acid, liquid measure, 

 than cyanide, and a half more water than acid. Weigh 

 the cyanide and wrap it in paper or a bag. Measure 

 the acid in a glass beaker, marked ounces on the side, 

 and pour it in an earthern jar or china bowl ; measure 

 the water and pour upon the acid. When everything 

 is in readiness drop the cyanide, paper and all, into 

 the liquids and close the frames quickly. 



