8 CONTROL SERIES NO. 130 



Example: A 5-8-7 fertilizer selling for $39.00 a ton analyzes: 



Total nitrogen 4.67 



Water-insoluble nitrogen 88 



Available phosphoric acid 7.43 



Potash 7.13 



Shortage: Nitrogen _...._ _. 33 X$2.00 =$0.66 



Available phosphoric acid 57 X 1.40= .80 



Total _.. $1.46 



Our calculated guaranteed value: 



Water-insoluble nitrogen = .88+. 11= .99X$8.00=$7.92 



Water-soluble nitrogen =5.00 -.99 =4.01 X$2.00 = 8.02 



Available phosphoric acid =8.00 X$1.40 = 11.20 



Potash = 7.00 X$0.80 = 5.60 



Total $32.74 



Approximate commercial shortage = (39.00-^32.74) Xl.46 =$1.74 per ton. 



Explanation of Table of Analyses 



Guarantee. The plant food guarantee or the grade of each fertilizer is made 

 a part of the trade name under the heading "Name of Manufacturer and Brand" 

 and is expressed as nitrogen, available phosphoric acid, and water soluble potash 

 and in that order. 



Mixtures Substantially Complying with the Guarantee. In addition to those 

 fertilizers which meet their guarantees in every respect, this table includes also 

 those mixtures which have one or more elements below the guaranteed per- 

 centage but have a shortage of less than $1 per ton. 



This table, in addition to the data mentioned in the next paragraph, contains 

 only results of analytical tests pertaining to the average amount of water in- 

 soluble nitrogen present in each brand, since this information is of value to tobacco 

 growers and other users of fertilizers containing a high percentage of this form of 

 nitrogen. 



Potash Forms. Tests for chlorine are made only on tobacco mixtures and on 

 those fertilizers which carry a guarantee of potash in forms other than muriate. 

 When the amount of chlorine present in any brand exceeds the tolerance allowed 

 for that brand, this fact is indicated by a footnote. 



