SOCIETY OF CENTRAL ILLINOIS. 289 



less poisonous than Paris orreen, as shown from its having been eaten 

 by [)ersnns without serious liarm. It is more adhesive to vegetation 

 and therefore not as readily washed away by rains. Its effects are 

 more permanent, as from its fine state of pulverization it is partially 

 absorbed by the leaves. The color that it imparts to vegetation 

 shows its application and may serve to prevent the careless use of 

 poisoned plants for food. In its condition of a very fine powder it 

 admits of a more thorough admixture, when used dry, and is more 

 easily kept in suspension in water." 



APPLICATION. 



As in the case of Paris green, London purple may be applied 

 either dry or wet. If dry, mix one part by weight of the poison to 

 forty parts of flour, and sift or dust on in the usual manner. In 

 water, it is safe to use one ounce of poison to five gallons; or, the 

 same proportion, one pound to eighty gallons. Either of these two 

 substances may be applied for the destruction of such leaf-eating 

 insects as do not affect fruits or vegetables, that are to be used soon 

 after the application. Potato beetles of various species, cucumber 

 beetles, canker worms, and the various leaf-eating larva^ that attack 

 the foliage of fruit or shade trees, may all be destroyed by the appli- 

 cation of these insecticides. There seems also to be no satisfactory 

 reason why their ajjplication to prevent the ravages to the codling 

 moth in the apple orchard, should not become general among 

 orchardists. Already the practice largely ])revails in the great fruit- 

 growing districts of Western New York, nnd is rapidly becoming 

 popular in other states. While arsenic is sometimes recommended 

 as a substitute for the arsenites above mentioned (Paris green and 

 London purple), it has the great ol)jectioii that it scalds the foliage 

 to a very much greater extent than either of the others. Still it 

 may sometimes be available when the others are not, and possibly 

 may occasionally, in the hands of judicious ])ersons, be preferable to 

 them for application over large areas, as it is soluble in heated water, 

 and hence does not clog the nozzle through which it is applied. It 

 may be easily prepared by simply dissolving in boiling water, in the 

 proportion of an ounce of arsenic to a cpiart of water, and then dilut- 

 ing the mixture thus formed in the proportion of one quart to fifteen 

 gallons of water. 



I'RF.rArTION- IN USING ARSENITES, 



Dr. J. A. Lintner, State Entomologist of New York, in his ex- 

 cellent first report, to which I am much indebted in the preparation 

 of these notes, gives the following precautions to]l)e taken in hand- 

 ling Paris green, which are equally ,^applicable^ to all poisonous 

 insecticides. 



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