40 



paste and strain; wet up the Paris green with a httle water into a 

 thin paste; mix the hme and Paris green and add the remainder of 

 the water. 



Formula 4. 



Lead arsenate or disparene, ...... 2 pounds. 



Water, . . . . . . . . .50 gallons, i 



Arsenate of lead acts slower as a poison than Paris green, and for that 

 reason is not so effective for killing insects on rapidly growing plants 

 like potatoes. It can be kept suspended in the water better than Paris 

 green. It does not burn the leaves, and sticks to the foliage better than 

 Paris green. Make a smooth, thin paste with the poison and a little 

 water, and add the remainder of the water and stir thoroughly. 



Formulas for Blights, — Bordeaux Mixture. 



Formula 6. 



Copper sulphate, ....... 5 poxmds. 



Fresh lime (unslaked), ...... 5 pounds. 



Water, ......... 50 gallons. ' 



Formula 6a. 



Copper sulphate, ....... 5 pounds. 



Hydrated lime (prepared or ground lime), . . . 6-7 pounds. 



Water, ......... 50 gallons.' 



Bordeaux mixture according to Formula 6 is prepared as follows : — 

 the copper sulphate is dissolved and the lime slaked in separate vessels. 

 A wooden or earthen ^'essel must be used for the copper sulphate, as 

 it corrodes iron. Each solution should then be diluted with half 

 the water, and then the cold, dilute sidphaie and milk of lime solution 

 quickly united and thoroughly mixed. Never pour concentrated solu- 

 tions together. If impracticable to pour the two dilute solutions into 

 the sprayer or mixing tank simultaneously, the dilute copper sulphate 

 solution should be first placed in the tank and the dilute milk of lime 

 solution quickly added with constant stirring. 



Best results are obtained if care is taken to add the water slowly 

 to the lime while slaking, but it should not be allowed to become 

 dry. The milk of lime must be strained, and this is best done while 

 still hot. A brass wire strainer of about 30 meshes to the inch (No. 50), 

 or a piece of cheese cloth backed by common window screen, may be 

 used. The best type of strainer can be made by naiUng together 

 four 1-inch boards about 7 or 8 inches wide and 12 or 15 inches long, 

 making a jjox open at both ends. One end of the box is then cut oft' 

 at a considerable angle, leaving one side shorter than the other. No. 

 50 brass wire strainer is tacked on to this end. Two cleats are nailed 

 to the other end of the box, long enough to more than reach across 

 the top of the barrel. When placed on top of a barrel with the wire 

 bottom down, all the solid particles from the solution are washed to 

 the lower side of the screen, thus avoiding clogging the whole surface. 



The most convenient method of preparing Bordeaux mixture is to 

 make stock solutions. For this purpose suspend 100 pounds of copper 

 sulphate in a bag near the top of a 50-gallon barrel and fill with water. 

 This should dissolve over night. In another 50-gallon barrel slake 

 100 pounds of .stone lime, dilute and strain and make up to 50 gal- 

 lons. A gallon of each solution well stirred Avill be equivalent to 2 

 pounds of copper sulphate or lime, as the case may be. For a 50- 



' An ordinary oil barrel holds about 50 gallons. 



