1 86 



THE AMERICAN ENTOMOLOGIST. 



such extracts from our Bulletin on the 

 Cotton Worm as bear upon them. The 

 machines here described will show very 

 clearly the more important principles that 

 should be followed, but improvements and 

 modifications will suggest themselves to 

 any planter who has some degree of me- 

 chanical skill. We have already (pp. 41-45) 

 given a full account of the best mode of 

 using London Purple and Pyrethrum pow- 

 der, and by way of prelude to the presen- 

 tation of these spraying and sprinkling 

 machines we quote what we said regarding 

 Paris Green : 



" Paris Green. — The nature and effects of this 

 poison are now too well and generally known 

 among planters to need consideration. Planters 

 have too often found in its use a path leading 

 from threatened ruin and bankruptcy to be much 

 influenced by theoretical arguments against it. 

 A study of its effects, based upon experience and 

 experiment, whether upon the plant or upon the 

 soil, shows that no harm results from its judicious 

 use.* My expectations in first suggesting its use 

 as a Cotton-Worm destroyer at the Saint Louis 

 meeting of the National Agricultural Congress in 



[Fig. 87.1 



Fountain Pump, 



pound to that quantity of water is more often 

 used, and considered most satisfactory. This is 

 sufficient for one acre of cotton, and the cost per 

 acre of a single application, including labor, va- 

 ries according to a number of circumstances, but 

 ranges from 25 cts. to 6octs.* It pays to add two 

 or three pounds of flour or starch to the mixture, 

 not only because of the greater adhesiveness 

 which they give to the poison (a very desirable 

 object, especially in wet weather), but because, 

 by their color, tliey help to indicate the quantity 

 that has been distributed. In using Hour it will 

 be found advisable to mix it first in a bucketful 

 of water and allow it to remain until it sours, the 

 object being to prevent it from forming lumps. 



"When applied in powder the green must be 

 mixed with other ingredients in order to render 

 it sufficiently economical and avoid injury to the 

 plants. These ingredients should be cheap and, 

 as far as possible, adhesive. Of the various mix- 

 tures that are used to-day and that have come to 

 my knowledge all maj' be considered good. The 

 proportion of the green to the diluents should be as 

 I to 25, though the mixture is often used stronger, 

 or as I to 18. Flour, or plaster, or cotton-seed 

 meal are used with equal success, or a combina- 

 tion of them, the proportion being immaterial. 

 Finely-sifted wood ashes may also be used as a 

 diluent, one of the most popular mixtures con- 

 sisting of one pound of Paris green, 6 lbs of wood 

 ashes, and about 12 lbs of flour. In all cases it 

 is advisable to add a small proportion, say from 

 one to two pounds to the above formula, of some 

 finely-powdered material of still 

 greater adhesive quality, as dextrine, 

 or gum arable, or slippery elm bark, 

 or rosin. The cost per acre of one 

 application of the dry mixture varies 

 from 50 cents to ft. 75, according to 

 the first cost of materials and differ- 

 ent modes of application, or, again, 

 to the size of the plants at the time 

 of the application." 



1872, and more confidently recommending it be- 

 fore the same body at Indianapolis in 1S73, have 

 been fully realized by the experience of the past 

 seven years. Complaints of its inefficacy are 

 readily traceable either to faulty application or 

 the use of an adulterated article. Its principal 

 disadvantages are its great cost, often increased 

 by the exorbitant profits demanded by mer- 

 chants, and the consequent temptation to adul- 

 terate or imitate the genuine article. f Another 

 disadvantage is the difficulty of keeping it sus- 

 pended in water, but this is easily overcome 

 either by the employment of an additional hand 

 to keep the water stirred up, or by adding to the 

 various pumps with which the poison is distrib- 

 uted a simple self-acting lever inside of the bar- 

 rel or other vessel containing it. This, together 

 with the motion of the pump, is sufficient to pre- 

 vent settlement. Its advantage over the other 

 arsenical poisons, besides its undoubted efficacy, 

 is that it is least liable to scald the leaves and to 

 cause the young bolls to shed. 



" If used in liquid suspension, a simple mixing 

 with water is sullicient in dry weather. If pure, 

 one-half pound to 40 gallons will answer. One 



* A discussion of this subject will be found in a work by 

 the writer entitled " Potato Pests," pp. 69-75. 



+ An easy way of testing the purity of Paris green is to put 

 about 100 grains in an ordinary wine glass and add thereto an 

 ounce of liquid ammonia. In proportion as there is little or 

 no sediment the green may be considered pure. 



" Before describing these machines, it may be 

 mentioned that the Fountain Pump, manufac- 

 tured by Mr Josiah A. Whitman, of Providence, 

 R. I., has been extensively used in the South for 

 applying liquid poison. These fountain pumps 

 (Fig. 87) are too well known to need any further 

 description. They are sold in the South for about 

 $10 apiece, including the rubber hose. The most 

 common mode of using them is the following : 

 A barrel containing the liquid is put on a cart or 

 wagon and drawn over the field. One hand is 

 employed, if necessary, to keep the poison stirred 

 up, while three others, each with one of these 

 pumps, apply the liquid from the rear of the 

 wagon, one taking charge of the three inner rows, 

 the others each aliout three more rows on either 

 side. In the use of this and of all other pumps 

 it is advisable to add a strainer to the lower end 

 of the hose in order to prevent impurities from 

 entering the valve. In an emergency, where no 

 machines are at command, these fountain pumps 

 do excellent service, and many prefer them to 

 other means of applying the poison. They are, 

 however, wasteful of material, and the poison is 

 more apt to get on to the bodies of those em- 

 ployed in their use than in most of the other 

 modes of sprinkling. 



" Most of the machines used for throwing liq- 



* The present year, Paris green averaged about 17 cents per 

 pound in Selma, Ala., and 40 cents in Columbus, Tex. 



