FORMULAE. 



205 



Ar senile of Lime. 



Arsenic, 1 pound; stone lime, 4 pounds; 

 water, 4 gallons. Boil half an hour then dilute 

 to 200 gallons with water. 



Paris Green. 



Paris green, 0.5 pound; lime, 1.5 pounds; 

 water, 50 gallons, or perhaps better: Paris 

 green, 1 pound; quick lime, 3 pounds; water, 

 250 gallons. 



Combined Bordeaux Mixture and Paris Green 

 or Arsenate of Lead. 



Add to the regular 50 gallon Bordeaux, 

 1 pound of Paris green stirred up thoroughly 

 in a gallon of water, and stir thoroughly after- 

 wards. If arsenate of lead is used, double the 

 amount may be added in the same way. 



Boiled Lime-Sulphur. 



Lime, 25 pounds; sulphur, 17.5 pounds; 

 water, 50 gallons. Boil 1 hour. Apply at once. 



Self-Boiled Lime-Sulphur {Scott's method). 



Sulphur, 10 pounds; stone lime, 15 pounds; 

 water, 50 gallons. Put the lime into a barrel 

 and pour over it 2 to 3 gallons of boiling hot 

 water, add the sulphur at once, then 2 or 3 

 additional gallons of the hot water. Stir 

 frequently. More water may be added if it 

 becomes too thick, but add as little as possible. 

 The cooking should take place in about 6 to 8 

 gallons of water. The mouth of the barrel 

 should be covered to retain the heat. When 

 slaked add the remainder of the water, i. e., 

 cool quickly. Strain. Apply at once. 



Lime-Salt-Sulphur. 



Best stone lime, 30 pounds; sulphur, 15 

 pounds; salt, 10 pounds; water, 50 gallons. 

 Slake the lime in hot water, then while hot add 

 the sulphur and enough water to make a thin 

 paste and boil for three-fourths hour, stirring 

 thoroughly, adding more water as it evaporates. 

 Then add the salt, boil an additional 15 minutes, 

 dilute with hot water, filter and spray hot. 



Warren gives the following method of prepa- 

 ration: Fresh lime, 15 pounds; flowers of 

 sulphur, 15 pounds; salt, 15 pounds; water, 

 45 gallons. Bring 4 or 5 gallons of water to a 

 boil in an iron kettle, mix the sulphur with hot 

 water, crushing the lumps, then put into the 

 boiler, add the lime in 4 separate parts, adding 

 cold water gradually to subdue the violent 

 boiling and prevent from overflowing. Finally 

 add the salt, boil 1 hour or more, stirring 

 frequently. Strain, dilute with the remainder 

 of the 45 gallons (about two-thirds) and spray. 



There are other formula? in which the pro- 

 portions vary somewhat. 



Potassium Sulphide. 



One pound to 50 gallons of water. To be 

 used at once, because it soon loses strength. 



Carbon Bisulphide. 



Use 1 pound to each 100 bushels of grain, 

 or 1 teaspoonful to each cubic foot of space. 



Mercuric Chloride. 



Solution of 1 part to 1000 parts of water. 

 To be used in glass or wooden vessels, never 

 in metal ones. For field use tablets may now 

 be purchased so that it is only necessary to 

 dissolve the requisite number in a given volume 

 of water. 



Seed corn may be exposed 20 minutes with 

 entire safety, wetting first in alcohol for a 

 minute or two. Unsprouted potatoes 40 min- 

 utes to 1 hour. 



Hydrocyanic Acid Gas. 



For treating dormant nursery stock, W. E. 

 Britton, recoinmends 1 ounce cyanide of potash, 

 2 ounces sulphuric acid and 4 ounces of water 

 for each 100 cubic feet of space. The acid is 

 poured into the water, never the reverse, on 

 account of over heating and danger of steam 

 explosions; the cyanide is added, and the room 

 shut up tight for half an hour. For greenhouse 

 fumigation Woods and Dorsett recommended 

 20 minutes' exposure using 0.075 gram to 0.15 

 gram cyanide of potash per cubic foot, depend- 

 ing on the kind of plants, ferns being very 

 sensitive, and violets rather resistant. Symons 

 has shown that dormant peach buds will endure 

 0.50 gram of potassium cyanide per cubic foot 

 (2 ounces per 100 cubic feet) for 60 minutes. 

 Apples will endure as much. The use of 0.30 

 gram per cubic foot for 30 minutes is scarcely 

 sufficient to kill all of the San Jose scale, but 

 0.30 gram for 45 minutes would be. 



Formalin (40 per cent Formaldehyde). 



1 pint to 50 gallons of water for smut of 

 wheat and oats; 



2 pints to 50 gallons for scab of potato; 



4 pints to 50 gallons for disinfection of soils. 

 The formalin should be taken from sealed 

 (fresh) bottles, as it loses strength readily. 



Hydrogen Peroxide. 



Use 1 part to 200 of water. Must be fresh 



Whale Oil Soap. 



This may be used for plant lice at the rate of 

 2 pounds per 12 gallons of water. Dissolve 

 in hot water. In greater concentration it 

 should be tried in advance on a few plants. 

 In proportion of 1 pound to 4 gallons of water 

 it is said to injure tender plants (J. B. Smith). 



