EXPERIMENTAL TESTS OF MACHINERY DESIGNED FOR THE DE- 

 STRUCTION OF THE COTTON WORM. 



lieport by W. S. BARNARD, Ph. D.* 



U. S. Department of Agriculture, 



Entomological Di vision. 

 Washington, D. 6'., August 15, 1883. 

 Sir : Under your direction I have prepared and hereby submit the 

 following report on the experimental tests made during the last three 

 weeks near Selma, Ala. 

 BespectfuUy, 



W. S. BABXAED, Assistant 



€. V. Biley, Entomologist. 



RET? ORT. 



The Cotton Worm machine described in the annual report for 1881-82, 

 and now subjected to field tests, is shown to be suited only for cotton 

 so planted that the rows are spaced apart very equally, since it lacks 

 adaptability to the usual great differences of interspaces between the 

 rows. Unfortunately, nothing very closely approaching ideal straight- 

 ness of rows or equality of width between them can be detected in the 

 South, even in such fields as are said to be " planted perfectly true."' 



* Letter of instruction. 



Department of AGRICULTURE, 



Division of Entomology, 



July 14, 1883. 

 Sir : You will proceed to Selma, Ala., on the 16th of this month to carry out in detail 

 the verbal instructions which I have given you. These are, chiefly, to take with you 

 or send all the machinery necessary to put together and operate the spraying machine 

 illustrated on Plate IX of our last annual report. You will test this machine thor- 

 oughly, in order to settle by experience the numerous points that have not yet had 

 practical field demonstration. Thus, the most satisfactory form of nozzle, whether 

 for London purple, Paris green, or kerosene emulsion, the number of rows it is found 

 best to spray at once, the relative effects of finer or coarser sprays, and particularly 

 the effect of petroleum, etc., etc. Be particular to ascertain the actual cost and 

 actual area covered by a given amount of liquid. You will spend no time In testing 

 other devices or modes of poisoning. 



Respectfully, 



C. V. RILEY, 



Entoinolo 



Prof. W.S. Barnard, 



Assistant, Entomological Division. 



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