INSECTICIDES AND FUNGICIDES, 13 



lise for insecticides is that which contains 8 per cent, 

 potash. Soft soap dissolves more quickly in hot than cold 

 water. 



Pyrethrum Powder. _ A product obtained by 

 grinding the buds or the flowers of a species of pyrethrum 

 to a fine powder. Used largely for making insect powders. 



Hellebore Powder. — A substance prepared by 

 grinding the roots of the False White Hellebore (Veratrum 

 album) to a fine powder. It is poisonous, and must not 

 be inhaled. To avoid injury to the operator it is best 

 mixed with water before using. 



Paris Green. — This is known as an ai-senical insecti- 

 cide (aceto-areenite of copper). The best form of it to use 

 is Blundell's Paris Green, a preparation sold in powder 

 and paste form. The latter is the safest to use, as the 

 powder, if inhaled, is highly poisonous. Requires to be 

 applied in a very fine, mist-like spray. A splendid insec- 

 ticide for fruit trees. Not soluble in water; can only be 

 mixed with it. 



Arsenate of Lead. — A combination of acetate of 

 lead (98 per cent.) and arsenate of soda (98 per cent.). 

 The two require to be dissolved in water, as advised fur- 

 ther on. 



Kerosene. — An American oil; also known as paraffin 

 and petroleum oil. Used in conjunction with soft soap 

 and boiling water to form an emulsion. Requires whilst 

 boiling hot to be beaten into a creamy-white fluid. May 

 be stored in corked tins or jars for years. 



Nicotine An extract of tobacco used for making 



various fumigating compounds. A deadly poison. Tobacco 

 juice, made by steeping tobacco in boiling water, lb a less 

 concentrated form of it. 



