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Carbon Bisulphide, CS 2 . 



As the formula indicates, this compound is made up of carbon and 

 sulphur, one atom of the former and two of the latter. In the pure form 

 it is a clear liquid with a pleasant odor, but when impure it is somewhat 

 colored and possesses a highly disagreeable smell. It boils at 64. 2° F., 

 and thus volatilizes or changes to a vapor or gas very readily at ordinary 

 temperatures. This gas ignites at a temperature of 297. 5 F. 



The vapors are very poisonous, and thus are very valuable in dealing 

 with grain weevils, and the pea bug; and also for overcoming subter- 

 ranean workers. Its use was first discovered in France, where it was 

 and is employed against the grape phylloxera. The wine districts there 

 were saved from complete annihilation by its introduction. 



Since the vapor is 2.63 times heavier than air, it tends to work 

 downward very rapidly, and will thus penetrate to some depth in the 

 soil. In dealing with grain pests the liquid is placed in shallow dishes 

 on top of the pile and then as the evaporation goes on, the vapor will 

 work downward and penetrate the- whole bulk. 



Dosage : (1) For grain weevils, use one pint (1^ lbs.) for every 1,000 

 cubic feet of space. Place in shallow pans on top of the grain, using at 

 least one pan in every 25 square feet of surface. Thus a bin of grain 25 

 feet long, by 5 feet wide, by 8 feet deep, would require 1 pint to be 

 distributed in five pans. Larger quantities would not be harmful and 

 would be more effective ; the fluid is cheap, therefore employ an overdose 

 rather than an insufficient quantity. 



(2) For pea bugs use 1 pint for every 100 bushels of peas.* 



(3) For subterranean workers (root maggots, etc.) inject small quan- 

 tities into the soil around the base of the infested plant, 2 or 3 teaspoons- 

 ful in a place. 



As with hydro-cyanic-acid gas, all openings should be well sealed to 

 prevent escape and waste. Inhalation should also be avoided as much as 

 possible, although small quantities breathed in will produce no harm 

 except in cases of a weak heart. Fresh air is the cure, and when one 

 begins to feel a dizziness, it is wise to seek at once the open atmosphere, 

 Before entering a room where it has been used, thorough ventilatiofi 

 should be given. 



Precaution : — As one volume of carbon bisulphide vapor mixed with 

 14.3 volumes of air forms a highly inflammable and explosive mixture, 

 never allow a light or even a spark, or a lighted pipe or cigar to be 

 brought near it. 



Carbolic Acid, Phenol, C 6 H 5 OH. 



This substance is an oxygen derivative of benzene, one of the mem- 

 bers of the aromatic series of the carbon compounds. It has a permanent 

 but characteristic and pleasant odor, which seems to be quite distasteful 



*See Ontario Agri. College Bulletin No. 126, p.p. 26-27. 



