246 REPORT UPON COTTON INSECTS. 



Our experiments show that poison mixed with flour alone adheres 

 nearly as well as the above-named mixture, resin and dextrine seeming 

 to have but little action. It was also found that flour can be diluted to 

 a certain extent by gypsum or land plaster. But poison mixed with 

 plaster alone adhered but little better than when applied with water. 



Another advantage gained by the use of dry poisons is that there is 

 less danger of injuring the cotton than when water is used. 



The great objection to this method of poisoning is its cost, the price 

 of the flour adding materially to the expense; and, also, no way has yet 

 been devised and brought into general use of applying dry mixtures as 

 rapidly and easily as liquid poisons may be applied. We believe, how- 

 ever, that unless some method is devised for throwing a spray of liquid 

 poison upon the lower surface of the leaves, where it will be less liable 

 to be washed off by rain, dry poisons will be found most practicable; 

 and we feel sure that the objections of the expense can, to a great ex- 

 tent, be removed. Further experiments are necessary to devise a cheaper 

 method of distributing powdered substances over plants, and to deter- 

 mine to what extent the flour may be profitably replaced by plaster or 

 some other cheap material. The cost of the flour can doubtless be les- 

 sened by using a poorer quality, which might be manufactured for the 

 purpose from inferior or injured wheat. If a machine could be invented 

 by which a mixture of one pound of Paris green and two pounds of flour 

 could be quickly and evenly distributed over an acre of plants, the same 

 end would be gained. 



The simplest method of applying dry poisons, and the one most gener- 

 ally used, is by means of a tin vessel holding about a gallon, provided 

 with a handle and having a bottom made of perforated tin. By means 

 of this the poison can be sifted over the plants. Tins, however, is a 

 slow process, as only one row at a time is poisoned. 



Some||)lanters practice sowing the mixture when there is a light wind, 

 being in this way enabled to poison several rows at once. Aside from 



the fact that the conditions favorable 

 for this method cannot be relied upon, 

 the poison cannot be as thoroughly 

 distributed as is desirable. 



A device has been invented by Mr. 

 J. W. Young, of Southfleld, Mich., for 

 dusting Paris green upon potato- vines; 

 by means of this, two rows can be 

 poisoned at once. The form is shown 

 in Fig. 55 : 



The weight of the apparatus is bal- 

 FIG. 55. Young's sifter. auced upon the shoulders by means 



of a neck-yoke, thus leaving the hands and arms free to move the 

 handles. Each handle is attached to a brush that works horizontally 

 across holes in the bottom of the can. The cans are adjustable to the 



