256 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



be made in daylight, as no artificial light of any kind is allowable. Even 

 electric lights may not be used, since when turning them on or off there 

 is aways danger of producing a spark, which would prove disastrous if 

 the vapour should be present in the proper proportion. Heated steam 

 pipes constitute another danger to be guarded against, and they should be 

 allowed to cool before the application is made. Electric fans must not 

 be run, as they very frequently give off sparks. It is safer to have no 

 heat of any kind in the building while the exposure is being made ; and 

 it is a matter of courtesy, as well as a precaution, to warn the owners of 

 adjoining premises of the nature of the work being done, and of the need 

 for care if the vapours should penetrate to their rooms to any extent. It 

 would be an added measure of safety to have a watchman to guard the 

 premises from the time the application is made until ventilation is 

 complete. 



Treatment of Seeds. 



Many kinds of grain and garden seeds are subject to the attack of 

 insects. Contrary to the assertions of many seedsmen, such insects do injure 

 the germinating power of the seed. Even if the embryo itself escapes 

 attack, which is by no means always the case, the supply of the reserve 

 food material upon which it depends wholly for its start in life is more 

 or less consumed by the pest, and the vitality of the young plant is pro- 

 portionally weakened thereby. The principal seeds attacked are Corn, 

 \Vheat, Rice, Peas, Beans, and Cow-peas, while vegetable Peas suffer 

 more or less. Experiment has not yet shown any insecticide equal to 

 carbon bisulphide for the destruction of all these seed insects. 



Method of Treatment. — Seeds designed for treatment with carbon 

 bisulphide should be placed in barrels, bins, or rooms, care being taken 

 especially to have the receptacle tight around the sides and bottom. 

 The cubic contents of the receptacle should be computed and carbon 

 bisulphide applied at the rate of from 1 to H lb. for each 1,000 cubic 

 feet of space, which is the capacity of a bin or room ten feet each 

 way. A barrel will require a larger proportional amount unless it is very 

 tight. The liquid is placed on the top of the seed in shallow pans or 

 soup plates, about a teacupful being placed in each. A small bin or barrel 

 may be covered sufficiently tight with heavy blankets or oilcloth. The 

 receptacle should be kept tightly closed from twenty-four to thirty-six 

 hours with perfect assurance that the germinating power of the seed will 

 not be injured. Rye, Millet, Barley, and Crimson Clover are most liable 

 to injury, and should receive the minimum of treatment. 



Fumigation Houses — In the large seed-growing districts special houses 

 are constructed for this work. The following description of the house 

 and the manner of treatment is given by Professor A. J. Cook : * — " The 

 house is made; air-tight ; even the door is made very close-fitting, and it is 

 made still closer by pasting paper over the edges upon closing it, after 

 filling the house with sacks of Peas. An air-tight flue at one end opens at 

 the very top into the building and at the bottom out of doors. A sort of 

 chute with an adjustable air-tight valve is arranged for the turning on of 

 the liquid. The liquid is turned on until the odour shows that the vapour 

 * Bull. No. 58, Michigan Agr. Exp. Sta. 



