Chemical Analyses of Fertilizers 189 



ammonia nitrogen are dear, they change the proportions 

 of these to correspond with the difference in price, in order 

 to retain the same selling price. 



This is an important point, since after a certain brand 

 has been shown to be better suited than another to their 

 conditions of soil, to change the formula, both in refer- 

 ence to the character and proportions, may mean to the 

 purchaser the difference between profit and loss. 



Evidence on this point can be obtained from the re- 

 ports showing the results of the analyses of the different 

 brands from year to year, and a careful study of these 

 shows that genuine manufacturers of fertilizers those 

 who make it their sole business, rather than a side issue 

 or an adjunct to another business can be fully de- 

 pended upon in this respect. They know that the farmer's 

 interest is their interest, and that their sales will depend, 

 other things being equal, upon the increased crop results 

 that the farmer secures ; that the permanency and success 

 of their business will depend upon the successful and 

 profitable use of their product ; and that they cannot af- 

 ford to and do not change their formulas from year to year, 

 either in proportion or quality of constituents, to cor- 

 respond with the changes in price of the materials. Their 

 brands can be depended upon to furnish practically the 

 same amount, kind and proportion of plant-food from 

 year to year. 



The value of a fertilizer depends upon the kind, quality 

 and form of plant-food, as shown by the analysis. Value 

 does not depend upon who the manufacturer is, or what 

 the statements may be concerning the usefulness of special 

 manipulation, nor to any great extent upon special formu- 

 las, unless the farmer has positive knowledge of the char- 

 acter of his own conditions. Formulas derived both in 



