AN IMPROVED SYSTEM. 



61 



Very few metals will withstand sulphuric acid without corroding. 

 For this reason all the common types of faucets are practically 

 worthless for drawing acid. There is 

 no faucet on the market that is alto- 

 gether satisfactory for this purpose, 

 although at the present time a manu- 

 facturing firm on the Pacific coast is 

 experimenting in the hope of perfect- 

 ing the necessary article. We have 

 met this difficulty in an entirely prac- 

 tical manner by attaching a three- 

 quarter inch iron pipe to the lower 

 side of the jar and regulating the flow 

 of acid by means of a large pinchcock 

 placed on a short piece of rubber tub- 

 ing at the end of the pipe (fig. 24, 1, 4, 

 and 5) . The flow of acid is rapid and 

 easy to control. Pure rubber is most 

 satisfactory and a fresh piece should 

 be substituted about every other night. 



The water is drawn from a faucet. 

 In order that this may be drawn on 

 the same side of the cart as the acid, 

 a pipe of the character shown in figure 

 23 is required. The faucet should 

 have an opening of about three-fourths 

 inch to allow a heavy flow and should be of such a type that a half 

 turn will give it a full opening. 



As fumigation is usually conducted at night a torch is placed on 

 the front of the cart to furnish a light by which to measure the acid 

 and water; one on the elevated platform is convenient for the man 

 measuring the cyanid. 



This style of cart is entirely practicable for almost all fumigation 

 work. The chemicals can be measured quickly and accurately with- 

 out any slopping of acid or water. The work is also easier on the 

 men in charge than under the old system. On ground which is so 

 rough that a wheeled cart can not be drawn, a portable table may 

 be used. Such a table as is shown in figure 25 can be easily utilized 

 for such a purpose. 



PROCEDURE. 



Five men are required to operate this system to advantage. Two 

 men pull the tents and kick in the edges around the bottom of the 

 tree. One man takes the measurements of the tree and determines the 

 dosage from a dosage schedule which he carries with him. After de- 

 termining the dosage he should empty the generator to be used for 

 that tree and have it in readiness bv the time the cart arrives. The 



Fig. 24. — Earthenware acid jar with attach- 

 ments for field use: 1, Jar complete; 5, in- 

 side view of lead-lined cover showing tube 

 at center; S, copper top for opening in 

 cover; ^ pinchcocli; 5, method of attach- 

 ing iron pipe to jar, and rubber tube on end 

 of pipe with pinchcock attached. 



