analysis in No. II shows it. Less blood and bone 

 could have been used in No. II, and more filler, but the 

 resulting analysis would have been still lower. 



If, however, the fertilizer is acidulated, the per- 

 centage of plant food may be low, as the weight of 

 the acid used displaces some of the material, yet the 

 fertilizer should be considered high grade on account 

 of the more soluble condition of its phosphoric acid. 

 Here the better form of plant food compensates for 

 the smaller quantity. If the acid phosphate should 

 revert to insolubility on account of the lime or other 

 bases in the soil, its purchase would be equivalent to 

 low grade materials, as the advantage of greater 

 solubility is largely lost and the total amount of 

 phosphoric acid purchased is small. 



THE " SIMPLES " AND HOME MIXTURES. 



The " simples " are the original materials, or the 

 bases of which factory mixed fertilizers are composed. 

 They are such materials as nitrate of soda, pure 

 blood, sulphate of ammonia, potash salts, bone, 

 phosphate rock, super phosphates, etc. Tankage 

 and the guanos are " simples, " as they are the bases 

 of manufactured brands. There are low and high 

 grades of the " simples " as well as of brands, and 

 guarantees should always be obtained by the buyer. 



Sometimes these materials can be purchased 

 cheaper separately than when mixed. Such is the 

 case if the buyer is near a seaport or near the source 



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