PRACTICAL HINTS TO NURSERYMEN WAU 
moist, but should not be drenching wet. Where only 
a few trees are fumigated, they are usually stood on 
the floor in bunches. When the desired number has 
been placed in the room, and the ventilators have been 
closed, they are ready for the gas. The chemicals are 
then prepared and placed, after which the doors are 
closed, and left the desired length of time. A _ half- 
hour is the minimum limit, but thoroughly matured 
dormant trees are not injured in the least if left an 
hour. The chemicals should be prepared and used 
strictly in accordance with the directions given in 
Chapter II. 
Other materials needed.—A pickle jar or china dish 
holding from two to four quarts is best adapted for 
holding chemicals for the generation of the gas in 
ordinary houses. Sometimes a larger vessel, such as a 
snuff-jar, is needed. A liberal supply of small manila- 
paper bags holding a pound or more are necessary. 
Where the amount of cyanide needed is known, it can 
be weighed, placed in manila bags, and kept in an 
air-tight can or other enclosure ready for use. Care 
should be taken not to weigh too much cyanide at a 
time, as the bags become saturated with moisture if 
long exposed to the air. It is best to weigh the cyanide 
at night or early in the morning, or even during the 
noon hour, rather than have it standing around for 
several days. A glass beaker, holding from a pint to 
a quart, with a graduated scale on the side in ounces, 
will be required for the acid and water. <A supply of 
acid should be kept in a carboy or other vessel. It 
should be drawn in an ordinary glass, china, or agate 
pitcher, as needed. For immediate use, a supply of 
