'220 IXSKCTU'IDKS, FUX(rIGIDES, AND WEED KILLEKS. 



■sickly for some time. To avoid this annoying action of l)lue vitriol, 

 produced after steeping (an action which is always dangerous because 

 the adherent liquid becomes concentrated), a second steeping must be 

 given, capable of removing this secondary action from the blue vitriol. 

 Kuhn was the first to wash the disinfected grain and immerse it in a 

 6 per cent milk of lime. This method, which suppresses all the draw- 

 backs of blue vitriol, has met with a wide response. It is in common 

 use in Germany. Steglich places the corn-seed in a basket, dips it 

 into the blue vitriol solution, takes it out and at once dips it into a 

 ■solution of carbonate of soda. The copper carbonate which forms an 

 insoluble layer I'ound the grain is without any injui'ious action on it, 

 but it is a very effectual protection against infection, w^hich may occur 

 after sowing. Hollrung altered this method ; he steeps the grain in a 

 vat containing only a 0"3 per cent solution of blue vitriol. After 

 stirring the grain for four hours he takes it out and washes it for thirty 

 minutes in a 0-4 per cent solution of milk of lime. The seeds are 

 then spread on the floor in a thin layer and frequently turned. Each 

 operation should be done in warm weather. In spite of all experi- 

 ments on steeping, on the concentration of solutions, and on the 

 temperature, Kuhn's process is used in actual practice, the steeping 

 in a blue vitriol bath being followed by a passage through milk of 

 lime. The dangers of too strong solutions being thus much diminished 

 reversion was made to solutions of 0"5-l per cent used in immersions 

 ■of short duration. This operation, always long wnth dilute solutions, is 

 thus greatly shortened. The following method most used in France 

 was recommended by Deherain and Loverdo and popularized by the 

 Minister of Agriculture. Dissolve 50-100 grammes (772-1543 grains) 

 of blue vitriol in 10 litres (2-2 gallons) of water ^ and dissolve this in a 

 vat containing 1 hectolitre (2| bushels) of corn-seed, then add water 

 until the grain is covered with a layer of liquid 4 inches deep. Stir 

 the mixture. Eemove the seed which float, then drain the remainder 

 in a basket. After an hour dip the grain into fresh water, and 

 ■dust with slaked lime (chaux fusee). To prevent any delay in 

 germination Bernard advises a steep of the following composition : 50 

 grammes of blue vitriol (772 grains), 300 grammes of nitrate of soda 

 (4632 grains), and 300 grammes of superphosphate (4632 gi-ains) in 10 

 litres of water. After a short immersion in this steep the grain is 

 pralined with ashes or slag. Seed-corn so treated has always shown 

 a certain advance in its growth, and given higher yields because the 

 plant finds after brairding a zone rich in nutritive substances. An 

 analogous result is obtained by the repeated spraying of wheat in a 

 heap. When all the grain is well impregnated with blue vitriol the 

 heap is dusted with slaked lime. This method has the advantage over 

 immersion of precipitating around the grain a strong layer of hydrated 

 oxide of copper, which adheres very well to the surface and prevents 

 ulterior infection by contaminated dung, but this process requires much 

 handling for it requires continual shovelling. 



^That is to say, at the rate of 5 lb. to 10 lb. of blue vitriol in 100 gallons of 

 water, and of this solution use 1 gallon for every bushel of seed-corn. — Tr. 



