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to many insects. In the undiluted form this acid is very active, and will 

 burn and blister the flesh and cause much pain, but in the diluted form, 

 as i part to 40 or 50 parts of water, it makes an important disinfectant 

 that is extensively used in medicine. In the form of an emulsion with 

 soap and water it is very useful in destroying the egg's and young- mag- 

 gots which infest onions, radishes, and similar garden crops. 



The emulsion is made thus : 



Carbolic acid 1 pint. 



Hard soap 1 pound. 



Water 1 gallon. 



Dissolve the soap in the boiling water, and while boiling add the acid 

 and continue the boiling for a few minutes, stirring thoroughly. Put the 

 emulsion away in a tightly closed vessel and label "Stock Solution of 

 Carbolic Acid— Poison." Before using, dilute 1 part of the stock solu- 

 tion with 50 parts of water. 



Carbolic acid is also, used in the form of what is known as "Carbol- 

 ized Plaster," in which case the acid is mixed with land plaster (gypsum), 

 road dust, air-slaked lime or some other diluting medium, and is then 

 sprinkled or dusted on in the dry state. 



Carbolic acid 1 pint. 



Diluent (land plaster, etc.) 50 pounds. 



This mixture is said to be very effective against flea beetles, cucumber 

 beetles, etc. 



Tobacco. 



A strong decoction that is very obnoxious to insects and at the same 

 time poisonous (nicotine) can be made from tobacco (stocks, refuse leaves, 

 sweepings, etc.), by steeping in water for a prolonged period. This could 

 be made a very valuable source of an insecticide by those people living 

 in a tobacco district, or near a tobacco or cigar factory. 



A good way to use the strong extract, although it can be sprayed as 

 it is after it is diluted with water to about the color of strong tea, is as 

 follows : 



Hard soap 1 pound. 



Water 8-10 gallons. 



Strong tobacco extract 1 



Dissolve the soap in boiling water, add the decoction, and then make 

 up to 8-10 gallons. 



White Hellebore. 



This is a powder obtained by grinding up the dried roots of a plant 

 known as Veratrum Album. The powder is of a light yellowish color 

 and possesses a rather pleasant odor, and contains as its active principle 

 a very powerful alkaloid called Jervine. It kills both by poisoning the 

 insect and by stopping up the breathing pores, and can thus be classed 

 as both a food poison, and a contact insecticide. Hellebore is much less 

 poisonous than the arscnicals and soon loses its poisonous action when 



