274 horticultukist's kule-book. 



the equivalent of from 94 to 97 per cent of sulphate of ammo- 

 nia. The rest is chiefly moisture. 



Nitrogen 20.02 Equivalent ammonia . . 24.30 



46. Sulphate of Potash. (Two samples.) 



The double sulphate of potash and magnesia is usually sold 

 as "sulphate of potash." 



Actual potash "^7.76 51.28 



Equivalent sulphate of potash 51.3 94.80 



47. Sulphate of Magnesia. 



Moisture at 100<=^ C. . . 29.01 Sulphuric acid .... 30.35 

 Magnesium oxide . . . 15.87 Insoluble matter . . . 6.29 



48. Nitrate of Soda. 



Nitrate of soda is mined in Chile and purified there before 

 shipment. It usually contains about 16 per cent of nitrogen, 

 equivalent to 97 per cent of pure nitrate of soda. It contains, 

 besides, a little salt and some moisture. 



Moisture 35 Sulphate of soda . . . 0.21 



Salt (sodium chloride) . . .23 Pure nitrate of soda . . 99.21 



49. Muriate of Potash. (Two samples.) 



Commercial muriate of potash consists of about 80 per cent 



of muriate of potash (potassium chloride) ; 15 per cent or 



more of common salt (sodium chloride), and 4 per cent or 



more of water. 



I. II. 



Actual potash 50.0 52.82 



Equivalent muriate 79.2 83.70 



50. German Potash Salts — Average of 11 Analyses. 



Moisture at 100° C. . . 13.14 Magnesium oxide . . . 9.25 



Potassium oxide . . . 21.63 Sulphuric acid .... 10.85 



Sodium oxide .... 13.76 Chlorine 35.63 



Calcium oxide .... 0.85 Insoluble matter . . . 2.08 



