violets are to be fumigated the dose would be one-tenth of a gram 
per cubic foot. A dose, therefore, for the even span house, containing 
4,646 cubic feet would be 4,646 multiphed by .1 equals 464.6 grams. 
To reduce this to ounces, divide the number of grams by 28.35 (the 
number of grams in an ounce avoirdupois). 464.6 divided by 28.35 
equals 16.38 ounces avoirdupois. It may be necessary to reduce the 
fraction of ounces to grains; 437.5 (the number of grains in an 
ounce) multiplied by .38 equals 166 grains. 
If double violets are to be fumigated the cubic contents would be 
multiplied by .15, thus: 4,646 multiphed by .15 equals 696.9 grams, 
divided by 28.35 equals 24.58 ounces avoirdupois. .58 ounce equals 
253 grains. In the case of a small space of less than 150 cubic feet 
the dose in grams should first be determined, and this, if necessary, 
can be changed to grains by multiplying the number of grams by 
15.43 (grains in a gram), thus: 30 (cubic feet) multiplied by .15 
grams equals 4.5 grams, multiphed by 15.453 (grains in a gram) 
equals 69.435 grains, or approximately 69.5 grains. The reduction 
to ounces or grains will not be necessary if metric weights are used, 
which is strongly urged. When the dose for certain plants in a 
given house, frame, or box is once obtained, it should be carefully 
recorded on the house or box, thus: 
Contents: 1,015 cubic feet. 
\ Ferns, .075 gram per cubic foot equals 76.1 grams. 
‘ Violets, double, at .15 gram per cubic foot equals 152.25 grams. 
If a scale weighing with avoirdupois weights is used, the dose 
should be recorded in ounces and grains. 
SELECTING A TIME TO FUMIGATE. 
Care should be taken to select a night when the houses can be 
ventilated the required time without injury to the plants and when 
there is little or no wind. 
PREPARATION OF THE HOUSE FOR FUMIGATION. 
On account of the very poisonous nature of the gas, it is necessary 
to arrange a number of ventilators, the more the better, so that they 
can be easily opened from the outside. It would be very dangerous 
to enter the house while it contains the gas. All broken glass should 
be replaced and holes stopped up; a thoroughly wet piece of news- 
paper will close a crack effectually or take the place of a broken 
glass if necessary. It is best not to permit the gas to get into fire 
pits or engine rooms; these should be cut off from the space to be 
fumigated. 
