394 



SCIENCE. 



[Vol. XIII. No. 329 



cigar-factories are generally easy to obtain, and, if fresh, are effec- 

 tive in destroying the pests mentioned. 



Bisulphide of carbon is a volatile substance used for destroying 

 grain insects, ants, the grape phylloxera, and other insects which 

 may be reached by a vapor. It is inflammable, and should never 

 be used in the vicinity of a fire. Benzine is another volatile sub- 

 stance, used for much the same purposes as the last. Gasoline 

 may also be mentioned in the same connection. 



Coal-tar has been largely used in the West for destroying Rocky 

 Mountain locusts, being placed on flat pans, on which the insects 

 jump and are caught. It is also employed to prevent the migra- 



opportunities ; but it is absolutely necessary that the first attacks 

 of the ravenous little creatures be promptly met. Do not delay a 

 single day, for they increase in numbers with marvellous rapidity ; 

 and one day is sufficient for millions of eggs to be laid, to repro- 

 duce in a short time larger hosts, even should we be successful 

 enough to destroy the original advance guard. Promptness in this 

 will save one-half the trouble and expense later on. In applying 

 insecticides, it should be borne in mind that " a little is as good as 

 a feast." It is not necessary to drown the insects with solutions, 

 or to bury them with powder, to kill them, — the least particle of 

 poison is sufficient to do its deadly work, — but it is necessary that 



LEGGETT'S POWDER-GUN. 



tions of the chinch-bug. A shallow V-shaped channel is made 

 with the corner of a hoe along the borders of the field to be pro- 

 tected, and tar poured in. So long as the tar does not dry out, the 

 immature chinch-bugs cannot cross it. 



Lime and plaster are excellent for use in preventing the depre- 

 dations of certain insects. Plaster may be dusted on melon and 

 other vines to drive off flea-beetles ; and fresh-slacked lime may be 

 dusted or sprayed (a peck to fifty gallons of water) on grapes, 

 peaches, etc., to prevent rose-beetle injuries. Gas-lime is some- 

 times recommended as an insecticide, but seems to be little used 

 in America. It is valuable as a fertilizer, and can be obtained at 

 little cost. 



" the least particle " and the insect come in contact. It is much 

 better to reach every portion of the plant or tree, underneath as 

 well as above, with a fine spray of fluid or a slight dusting of pow- 

 der, than to apply liberally in some parts and carelessly overlook 

 others, as is the too general custom. To fight insects effectually, it 

 must be done thoroughly, and every inch must be covered. Be- 

 sides, there is much less danger of burning or injuring the leaves 

 and fruit by light applications. 



The recently improved implements for applying powders or 

 fluids are great economizers, covering larger surfaces with less 

 material, doing it with greater speed, and reducing the danger 

 of injury to plants to a minimum. Among them we will mention 



DOUBLE-CONE POWDER-BELLOWS. 



VAPORIZING-BELLOWS. 



Soluble phenyl and paraffine-oil are two English insecticides 

 frequently recommended for trial here, but which are as yet little 

 used. For the following facts concerning the newer inventions for 

 the application of insecticides we are indebted to Peter Hender- 

 son & Co., seedsmen of this city. 



The enormous damage done by insects to our fruits, vegetables, 

 grain, etc., is almost beyond belief, — amounting, it is claimed by 

 competent authorities, to from $200,000,000 to $250,000,000 per 

 annum in the United States alone, — and their ravages are steadily 

 increasing. Fortunately the extensive experiments in insecticides 

 and implements for applying them enable us to fight them so well 

 that the damage done is scarcely felt when the most is made of our 



Leggett's powder-gun, in which a rapidly revolving fan-wheel 

 blows the powder through a long tin tube with such force that it is 

 widely and lightly distributed over a large surface. Sectional tubes 

 can be added, so the powder will go up into the tallest fruit-trees ; 

 and, as the under side of the leaves are reached as well as above, 

 it is an exceedingly effectual implement. A short curved tube 

 comes with it for applying powders to low-growing plants, by 

 which the under side of the foliage is reached as well. The supply 

 of powder can be regulated to such a nicety, that Mr. Leggett 

 claims he can make half a pound of London purple cover an acre. 

 Woodason's improved double-cone bellows is also worthy of special 

 mention. It is impossible to clog it, as a series of perforated tubes 



