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Phosphoric Acid in Mixed Fertilizers. — Of the total phosphoric acid 

 found in the complete mixed fertilizers, 83.76 per cent, was in available form 

 and 57.9 per cent, of the available phosphoric acid was in water soluble form. 

 In the ammoniated superphosphates 84 per cent, of the total phosphoric acid 

 was in available form and 55 per cent, of the available phosphoric acid was 

 in water soluble form. These figures show a satisfactory availability. 



Potash in Complete Fertilizers. — The average complete fertilizer 

 contained 1.74 per cent, of water soluble potash. The larger proportion of 

 the brands (namely, 72) had but 1 per cent, of potash, 12 had 2 per cent., 8 

 had 3 per cent., and 12 had a minimum of 4 per cent, guaranteed. Out of a 

 total of 108 brands analyzed, 32, or 30 per cent, of the total number, failed 

 to meet the minimum potash guarantee. The manufacturers are no doubt 

 having some difficulty in finding potash salts free from chlorine. Most brands 

 contain their potash both as muriate and as sulfate, this being true even for 

 brands designated for tobacco and potatoes. The small amount of potassium 

 oxide present, however, eliminates any serious damage resulting to quality, 

 due to chlorine being present. 



LIME COMPOUNDS. 



Forty-three samples of lime products have been examined. Thirty-five 

 analyses have been made, representing 25 distinct brands. The average per- 

 centage of calcium and magnesium oxides found in the more active forms of 

 lime, such as the hydrated or slaked limes, has been 63.46 per cent, and 3.98 

 per cent., respectively. Lime ashes have shown on the average 44.65 per cent, 

 of calcium oxide and 1.64 per cent, of magnesium oxide. It will be seen by the 

 footnotes that 3 samples of lime ashes have shown unusually large percentages 

 of potash. Two of these brands were submitted by the manufacturer. Al- 

 though perhaps one would not be justified in assuming that the samples had 

 been selected on account of the large proportion of wood ashes which were 

 present, yet the fact should not be lost sight of that the potash content is very 

 much in excess of the average for this product, which would probably not 

 amount to one-half of 1 per cent. 



Fine ground limestone has tested on the average 44.75 per cent, of calcium 

 oxide and 4.44 per cent, of magnesium oxide. The guarantees of calcium and 

 magnesium oxides on all the lime products have, as a general rule, been pretty 

 well maintained, the few exceptions being easily noted in the tables of analyses. 

 The advance in the cost of lime products has not kept pace with that for com- 

 mercial fertilizers, and as a rule the slight increase has been due to increased 



