6 BULLETIN" 197, U. S. DEPARTMENT OF AGRICULTURE. 



but it is necessary to use a good grade and at least 20 per cent more of 

 this form of lime, as it contains a high percentage of moisture. 



Place enough water in the cooking vessel to finish with 50 gallons 

 of the solution. Bring the water to the boiling pointy start the 

 agitator, if the plant is equipped with one, then put in the lime 

 and immediately add the sulphur. The mixture should be stirred 

 vigorously either mechanically or by hand until the lime is slaked. 

 Agitation should be continued throughout the time of cooking, which 

 should not exceed one hour. If the solution is to be barreled without 

 filtering, it should be drawn off immediately and allowed to run 

 through a 30-mesh strainer into the barrels. The agitation should 

 continue until all the solution is drawn off, so that there will be an 

 equal distribution of the sludge in the different barrels. 



PREPARATION OF HIGHLY CONCENTRATED LIME-SULPHUR SOLUTION. 



From the experiments above reported, it is evident that a highly 

 concentrated lime-sulphur solution may be made by using the lime 

 and sulphur at the ratio of 1 to 2 as is usually recommended, but 

 with reduced quantities of water. The formula used in the com- 

 mercial lime-sulphur manufacturing plants visited and also in the 

 foregoing experiments is as follows: 



Fresh stone-lime pounds . . 80 



Commercial ground sulphur do 160 



Water to make the finished product gallons. . 50 



While there is about 50 per cent in volume of sludge after allowing 

 this solution to settle for 24 hours, there is only about 5 to 10 per cent 

 in volume of insoluble materials. These consist of sulphites, free 

 lime, free sulphur, magnesium compounds, etc., varying with the 

 kind of lime used and other conditions. « Solutions prepared by this 

 formula should test on an average 33° to 34° Baume. 



RELATIVE COST. 



Commercial ground sulphur can be bought in car lots for about 

 $1.50 per hundred pounds, and lime at about 60 cents per barrel. At 

 these prices the highly concentrated solution can be made at the 

 following cost per barrel: 



80 pounds lime at 60 cents per barrel $0. 20 



160 pounds sulphur at $1.50 per hundredweight 2. 40 



Labor and fuel, estimated 70 



Total cost per barrel of 50 gallons 3. 30 



This does not include interest and wear on outfit, and cost of 

 containers for storing. At the foregoing prices of ingredients the 

 high-test concentrate would cost about 98 cents more per barrel than 

 the lower-test concentrate made by the 50-100-50 formula. 



WASHINGTON : GOVERNMENT PRINTING OFFICE : 1915 



