The Composition and Use of Fertilizers. 2G7 



this proper mixing can be accomplished only by means not at the 

 command of farmers. Such statements are misrepresentations, 

 based either upon the ignorance of the person who makes them or 

 upon his anxiety to sell mixed goods. Nitrate of soda, for illus- 

 tration, does its work in plant nutrition in exactly the same manner 

 whether it is added to the soil as part of a mixture or whether the 

 ingredients of the mixture are applied separately. The availabil- 

 ity of plant food is not usually affected by mixing. Other condi- 

 tions determine whether a fertilizer shall be applied in mixed form 

 or in separate materials. 



G. To What Extent Home Mixing is Practicable. 



The conveniences needed to do one's own mixing are the follow- 

 ing: A tight barn floor, or earth floor that is hard, smooth, dry 

 and under cover; platform scales, shovel, iron hand-rake or hoe 

 and a sand screen. Farmers are advised, if they do their own mix- 

 ing, not to attempt to treat bones or rock with sulphuric acid (oil 

 of vitriol), but to purchase their superphosphate from the manu- 

 facturer. 



The advantages connected with having the mixing of fertilizers 

 done at a factory are the following: First, the mixing is apt to be 

 more thoroughly done at the factory. Second, the factory should 

 be able to do mixing in large quantities more economically, since it 

 has all facilities required. As a rule, it costs the farmer from 

 $2.50 to $3 to have the mixing and rebagging done at a factory for 

 each ton of materials. 



When the farmer prefers to purchase separate materials and do 

 his mixing at home, the following suggestions may be helpful: 

 If one has purchased the different materials in the right weights, 

 such as he wants to use for mixing, then no weighing is necessary, 

 as he has simply to mix all the materials he has. If he makes dif- 

 ferent mixtures, then the different materials should be weighed 

 accurately. If the material is at all lumpy, it should be sifted 

 with a sand screen, the lumps separated and then pulverized before 

 being added to the pile of fine material. When the materials have 

 been thus prepared, the most bulky material is spread out upon the 

 floor in an oblong pile that varies from G to 10 inches in depth. 

 The top is leveled off and then a layer of the next material is put 

 on, not quite so thick, and so on until the different constituents 

 have been added to the pile, care being taken to make such material 

 cover the one under it evenly over the whole surface. Then, one 



