The Composition and Use of Fertilizers. 313 



(2) Bone Phosphate of Lime. Guaranteed. Rule. Multiply 

 the given amount of hone phosphate of lime by 0.46 and this prod- 

 uct by the price of one pound of phosphoric acid in bone (see price 

 list on page 309). 



Example: What is the commercial valuation of one ton of 

 fine bone containing 50 per cent, bone phosphate of lime? 



50 x 0.46 = 23, the per cent, of phosphoric acid in the bone. 



23 x 3i cents = 80.5 cents x 20 = $16.10 a ton. 



(c) Materials Containing Potash. 



(1) Sulphate of Potash. Rule. Multiply the test per cent, sul- 

 phate of potash by 0.54 and the product by the price of one pound 

 of potasli in the form of sulphate (see price list on page 300). 

 Multiply this product by 20. 



Example: What is the commercial valuation of one ton of 

 sulphate of potash which tests 50 per cent, (low-grade) sulphate? 



50 x 0.54 = 27 per cent, of actual potash. 



27 x 5 cents = $1.35, value of 100 pounds of sulphate of potash. 



$1.35 x 20 = $27, value of one ton of sulphate of potash testing 

 50 per cent, sulphate. 



Example: What is the valuation of one ton of sulphate of pot- 

 ash which tests 95 per cent, (high-grade) sulphate of potash ? 



95 x 0.54 = 51.3 per cent, of actual potash. 



51.3 x 5 cents = 256.4 cents x 20 = $51.30 value of one ton of 

 sulphate of potash testing 95 per cent, sulphate. 



When the per cent, of actual potash is given, the first step can 

 be omitted, and the per cent, of actual potash multiplied by the 

 price per pound and then by 20. 



(2) Muriate of Potash. Ride. Multiply the given per cent, of 

 muriate by 0.63 and the result by the price of one pound of potash 

 in the form of muriate (see price list on page 309). Multiply 

 this result by 20. 



Example: What is the valuation of one ton of muriate of pot- 

 ash testing 85 per cent, muriate? 



85x0.63 = 53.55 per cent, of actual potash. 53.55x4 cents 

 = 228 cents x 20 = $45.60 a ton. 



.Second Method for Making Commercial Valuations of 

 Mixed Fertilizing Materials. 



Mule. Multiply the given per cent, of eaeli constituent (nitro- 

 gen, phosphoric acid and potash') by its list price, add the products 

 and multiply the sum by 20. 



