TESTS OF MACHINERY FOR KILLING COTTON WORM-. 47 



supports the hung -pipe and slides in eyes situated diagonally with re- 

 ference to the hnng-pipe. In the second, the pipe-top is supplied by a 

 flexile piece of hose, and is supported by a long slide-rod on <>; 

 twoof its sides, and inserted through Loose eyes placed diagonally from 

 the course of traction, as in the foregoing case. In the third Instance 

 the top is similarly supplied by a hose, but is hung by a peculiar locked 

 hook, eye, or loop which glides loosely on a stiffly-set diagonal bar. The 

 simple wooden A-fraine answers, and a series of small sloping metal bars 

 of gas-pipe were arranged on a wooden cross-bar. This device worked 

 well. Many kinds of winders would apply, but a simple plan is to wind 

 the small rope or cord around a pair of large eye-screws placed 3 inches 

 apart. The set line can be attached at any pjoint along the sliding 

 parts. Behind the proximal end of the range, through which any 

 pipe-top is to be allowed to slide, the line may pass through a large 

 screw-eye and thence to an extension of the pipe-top above the axis on 

 which it is hung. Then the pipe may be drawn to this place, and by an 

 extra pull its top will be brought down to the eye and the lower parts 

 of the pipe will be tilted upward above the plants for turning, when this 

 feature is desired. 



Concerning the use of kerosene upon cotton, the following should be 

 stated: About 10 gallons were applied, half undiluted and half in 

 emulsion variously diluted. The undiluted petroleum destroyed about 

 10 per cent, of the foilage sprayed by it. The undiluted milk-kerosene 

 emulsion ruined only about 2 per cent., and this diluted injures less and 

 less according to the attenuation, but all treated was injured to at least 

 a slight extent. The sprays were hardly satisfactory, as the tubing 

 would not permit the high pressure necessary for a very fine mist, and 

 the indications are that with the finest spray the strong kerosene and its 

 slightly diluted preparations may possibly yet become used, in proper 

 hands with great caution, upon the crop, but additional experimental 

 tests are needed. 



The apparatus taken, with the different machines constructed at Selma 

 and overcoming the objections herein set forth, have been shipped to the 

 Department. 



The leading conclusions from the experiments upon the special points 

 in my instructions may be extracted from the above and briefly sum- 

 marized as follows : 



At Selma, I operated the machine taken from the Department and 

 tested the points in question, so far as circumstances permitted. The 

 distinctive feature of the machine, its stiff supporting pipes, unfitted it 

 for the work to be accomplished. As fields could not be found having 

 rows practically of the same regular width as the spaces at which the 

 downward pipes were held stiff by their supporting pipe, that permitted 

 no independent lateral adjustment of the tops <>t' the hanging pipes with 

 reference to each other or to the rows having different or varying widths, 

 this vital impediment at the outset frustrated its use and the obtain- 



