METHODS OF HANDLING CE1 2 \ 
The element of beat due to the mixing of the acid and water is rec- 
ognized as an important factor in generating the gas. According to 
('. P. Lounsbury very nearly the maximum amount of heal is evolved 
when equal volumes of acid and water arc used, and he advises against 
the use of more than 2 volumes of water to i of acid. 
The point in question is one of those now under* investigation in 
California l>\ agents of this Bureau. Until conclusions are reached 
the writer would recommend that the chemicals he used in the propor- 
t ion of 1 part of cyanid, 1 part of acid, and :\ parts of water, or l-l-.'5. 
'Phis formula i^ recommended for the present on account of results of 
experiments reported herein and upon which the table given in the 
appendix is based, being obtained with an average of 3 parts of water 
to 1 of acid. Future experiments may justify the California prac- 
tice from the standpoint of danger to the foliage from the use of the 
smaller amounts <A' water. In the experience of t tie writer as reported 
herein, the injury to the foliage has been too slight to show tiny rela- 
tion to the proportion of the chemicals, 
PROCEDURE. 
METHODS OK HANDLING TENTS. 
Sheet tents. — Octagonal sheet tents, or covers, are placed in position 
over trees by means of the changing poles and derricks which have 
been described. A tree which measures in extreme height between 
30 and 35 feet can be covered and made entirely ready for the genera- 
tion of the gas in less than two minutes if the work is not interfered 
with by the too close planting of trees. Smaller trees usually require 
from one to two minutes, according to size. When the changing poles 
are used (Plate II, figs. 1, 2; Plate III, figs. 1-5) in covering small 
trees, one man on each side of the tree places the ring over the end of 
his pole if catch rings are used, or if not, makes a double fold of the 
cloth over the end of the pole and makes a half-hitch over it with the 
rope to prevent it from slipping off. With the pointed end of the 
pole on each side about opposite the center of the tree they then raise 
the end of the pole and attached tent about 8 feet, or until the poinlcd 
ends hold without slipping, and, holding on to the rope, step forward 
and away from the tree and pull the tent into position. Some opera- 
tor^ prefer,after attaching the tent to the end of t he pole, to stand with 
one foot on the pointed end and raise the pole entirely by means of the 
rope. Knots tied in the ro pes at convenient intervals near the end 
are of great assistance in pulling. If the trees are so large that they 
require tents too large and heavy for handling by two men and yet 
not large enough to require the use of derricks, a third man maybe 
employe.d to advantage. The edge of the tent is made fast to the 
a Agricultural Journal (Cape Town), L902, p. 4. 
