20 
HYDROCYANIC-ACID GAS FUMIGATION IN CALIFORNIA. 
have used lampblack and turpentine, or a soft, flexible paint, with 
satisfaction. The first line marked should be the one running 
through the center of the tent. When many tents are to be prepared, 
the use of a stencil large enough to include a complete line of figures 
on one side will facilitate the operation. The numerals should be 
not less than 5 or 6 inches long. 
POLES AND DERRICKS. 
Two wooden poles or derricks are used in placing tents over trees. 
No absolute statement- can be made as to when poles should be 
employed or when derricks. The practice is to use poles when- 
ever possible. 
This has resulted, 
in general, in the 
use of poles with 
tents up to 45 feet 
in size and of 
derricks with the 
larger sizes. Some- 
times poles are 
used with tents of 
48-foot or 50-foot 
sizes, but this is 
difficult, especially 
if the trees are tall 
and narrow rather 
than 1 o w and 
broad. Preferably 
the poles should 
be 6 inches to a 
foot longer than 
the height of the 
trees. The two 
lengths of poles in most common use are 14 feet and 16 feet. Twenty- 
foot poles are occasionally required. These poles average from 2 inches 
to 2\ inches in diameter, are rounded, and made of straight-grained 
Oregon pine. The lower end is slightly sharpened to secure a ready 
hold in the ground. The upper end, to which a rope is attached for 
erecting the poles, preferably is also bluntly narrowed after one of 
the methods shown in figure 4. This figure also shows two convenient 
methods of attaching the rope. The end of a is narrowed about one- 
half inch on all sides for 3 or 4 inches. This allows it to slip easily 
through the rings in tents. The rope is tied in a shallow furrow 6 or 
7 inches distant from the end. In h the end of the pole is merely 
rounded, while the rope occupies an auger hole through the center 
Fig. 4. — Ends of hoisting poles used in placing tents over trees: a, Used 
with tents where rings are present: 6, used with tents having no rings. 
(Original.) 
