ENRICHING SOIL COMMERCIAL RESOURCES 99 



tilizers (remembering that 1 per cent means one 

 pound in a hundred, or twenty pounds in a ton) : 



No. 1. GUARANTEED ANALYSIS 



Nitrogen 1.60 to 2.00 per cent 



Phosphoric acid available . 7.00 to 8.00 " " 



Potash 2.00 to 3.50 " " 



Cost per ton, $29. 



Multiplying the lowest figure representing the 

 per cent of the given element by 20, and calcu- 

 lating the value from the price per pound, we 

 have in No. 1 : 



Nitrogen . . .1.60X20= 321bs.@15c. = $4 80 



Phosphoric acid 7 X 20 = 140 lbs.@ 5c. = 700 



Potash .... 2 X20= 401bs.@ 5c.= 2 00 



Commercial value per ton $13 80 



156. Another example of computation may 

 be taken : 



No. 2. GUARANTEED ANALYSIS 



Nitrogen 3.30 to 4.00 per cent 



Phosphoric acid available . 8.00 to 10.00 " " 



Potash 7.00 to 8.00 " " 



Cost per ton, $38. 



Its value is calculated the same as No. 1: 



Nitrogen . . .3.30X20= 66 lbs.@15c. = $9 90 



Phosphoric acid 8. 00 X 20 =160 lbs.@ 5c.= 8 00 



Potash . . . . 7.00 X 20 = 140 Ibs.@ 5c. = 7 00 



Commercial value $24 90 



