142 DESTEUCT1VE INSECTS OF VICTORIA: 



found. I have received samples of water-proof cloth from the United 

 States Water-proof Fiber Company, 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 pur- 

 pose, 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 feet high but it is not strong 

 enough for large-sized tents. At my request the company manu- 

 factured a tent about 12 feet high from this grade of cloth, 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 Company, 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 purpose. 



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 upon a 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 Wolfskill Fumigator. This apparatus was designed by Messrs. 

 J. W. Wolfskill and Alexander Craw, of Los Angeles, and is the first 

 that has been used with success upon the largest orange trees. A good 

 idea of its appearance is given in Fig. 1 7. 



This fumigator consists of a strong wooden frame mounted on a low 

 waggon or truck ; in the centre is a tall mast, the bottom of which 

 rests upon the waggon reach, which is strengthened by iron braces 

 attached to the side pieces of the frame. The mast is placed between 

 two pieces of pine timber and a stout iron pin passes through these pieces 

 and through the mast. The bottom of the mast is kept in place by two 

 blocks of hard wood bolted to the reach on either side of the mast ; their 

 inner ends are concave, so as nearly to encompass the lower end of the 

 mast. For staying the mast, four iron rods are attached at one end to 

 the four corners of the frame on the waggon, while their upper ends are 

 attached to an iron clamp which encircles the mast a little above the 

 middle of the latter. 



