126 REPORT OF THE COMMISSIONER OF AGRICULTURE. 
thus produced indicate that it can never be successfully used for the destruction of 
insects on trees. 
THE TENT, 
The tent used in inclosing the tree is of the usual circular form, with a conical 
or dome-shaped roof. Ti is usually made out of heavy bed-ticking, and is afterward 
thoroughly oiled with boiled linseed oil; care should be exercised not to leave the 
tent folded or rolled up while still damp with the oil. A tent belonging to Mr. J. 
W. Wolfskill, of this city, had been recently oiled, and when nearly dry was rolled 
up and thrown upon. the ground where the sun shone upon it ; this was in the fore- 
noon, and when it was unrolled tne next morning the greater part of it was found 
to be charred, as if by fire. 
It would be desirable to use some kind of ready-prepared cloth for making the ~ 
tent, but thus far no substitute for the oil-cioth has been found. I have received 
samples of water-proof cloth from the United States Water-proof Fiber Com- 
pany, of New York, but even the heaviest grade, although evidently water-proof, is 
far from being air-tight. A sample of twilled sheeting, prepared especially for this 
purpose, is much closer in its texture than the above, but is not air-tight; they 
offer to furnish it at about 10 cents per yard, the heavy bed-ticking referred to 
above costing in Los Angeles about 19 cents per yard. 
I have also received samples of rubber cloth manufactured by the Boston Rubber 
Company, of Boston, Mass. Their lightest and cheapest grade is a thin black 
cloth, which they offer to furnish and make into tents of any desired size, and with 
the seams closed up; the price would be about 23 cents per yard. This grade 
might answer for small tents—those not more than 5 or 6 feethigh—but itis not 
strong enough for large-sized tents. At my request the company manufactured a 
tent about 12 feet high from this grade of aS but found that it was not strong 
enough for the use I intended to make of it. 
They also sent three other grades of rubber cloth manufactured by them, and 
costing from 50 to 65 cents per yard made into tents; but it is doubtful that either 
of these grades would be strong enough for making large-sized tents. 
I have also received samples of rubber cloth from the Goodyear Rubber Com- 
pany, of San Francisco. Their light gossamer cloth is evidently not strong enough 
for making large-sized tents; its price is about 60 cents per yard. Their black 
rubber sheeting is the best that I have seen for this purpose, but the price, 54 cents 
per yard, would doubtless prevent its being used for this purposes 
APPARATUS FOR OPERATING THE TENT, 
Where small trees are to be operated upon a sheet might be used for the purpose 
of confining the gas; or the sheet could first be sewed in the form of a sack, which 
could be easily slipped over a small tree from above, the operator standing on the 
ground, or upona step-ladder. For operating on large trees, however, a device of 
some kind must be used for putting the tent on the tree, and also for removing it 
again. 
“The MeMullen Tent.—This tent was originally devised by Mr. W. G. McMullen, 
of Los Angeles, and is designed for operating on trees not over 12 feet high. It 
consists of two upright wooden supports or legs, the upper ends of which are at- 
tached to the opposite sides of a circle made of round iron or steel rods ; this circle 
is intended to pass around the inside of the tent at the junction of the roof and 
sides, and is supported by iron braces passing to the wooden supports or legs. 
The rafters or supports of the roof of the tent are three in number, and their upper 
ends fit into holes bored into a circular block of hard wood, which is retained in its 
lace by the weight of the tent; the lower ends of two of these rafters are attached 
o the circle at the upper ends of the two braces on one side of the circle, while the 
lower end of the third rafter is attached to the circle at the upper end of the oppo- 
site wooden support, the three rafters thus forming a tripod. They should be per- 
fectly straight instead of bowing outwardly. 
The tent itself should be made several inches larger all around than the frame on 
which it is to be placed, to allow for shrinkage when oiled. For the purpose of 
holding the tent in its place on the frame, narrow strips of cloth may be sewed 
around the inside of the tent where the circle and rafters are to pass, the strips be- 
ing wide enough to permit the circle and rafters to pass between them and the tent 
itself; or, what is still better, they may be sewed in the form of long tubes, through 
which the circle and rafters may afterward be passed. 
On one side of the tent, midway between the two wooden supports, the tent 
itself is slit from the circle to the bottom of the tent, and a strip of cloth 
about 20 inches wide is sewed t6 the tent along either side of this opening, ex- 
