28 



Three samples of dissolved bone black have been 

 Dissolved examined and all were found of good quality. The 

 Bone pound of available phosphoric acid from this source 

 Black, has cost on the average 7.41 cents. 



Seven samples of acid phosphate have been analyzed 

 Acid and the available phosphoric acid guarantee has 



Phosphate, been maintained in all but one instance. There 

 were no commercial shortages. The pound of 

 available phosphoric acid from this source has cost on the aver- 

 age 5.69 cents. 



Six samples have been examined and the available 

 Basic Slag phosphoric acid in all but one sample has run some- 

 Phosphate, what under the amount guaranteed. There has 

 been a commercial shortage in only one instance, 

 however, and that was less than 50 cents per ton. An excess 

 of insoluble phosphoric acid has made up the value of the de- 

 ficiencies in available phosphoric acid. The pound of available 

 phosphoric acid (by AVagner's method) from basic slag has cost 

 on the average 5.79 cents. 



Conversion Factors. 

 The writer has been asked by a number of large users of 

 fertilizers to publish in the fertilizer bulletin a table of conver- 

 sion factors by means of which the amount of plant food may 

 be calculated from the various chemical compounds in which 

 they are contained. 

 To change: — 

 Nitrogen to ammonia, 

 Ammonia to nitrogen. 

 Nitrate of soda to nitrogen. 

 Nitrogen to nitrate of soda, 

 Nitrate of potash to nitrogen. 

 Nitrogen to nitrate of potash, 

 Sulfate of ammonia to ammonia. 

 Muriate of potash to actual potash, 

 Actual potash to muriate of potash. 

 Sulfate of potash to actual potash. 

 Actual potash to sulfate of potash. 

 Nitrate of potash to actual potash. 

 Actual potash to nitrate of potash. 

 Carbonate of potash to actual potash. 

 Actual potash to carbonate of potash, 

 Bone phosphate to phosphoric acid. 

 Phosphoric acid to bone phosphate. 



Explanation of Table of Analyses. 

 In the first column will be found the name and address of 

 the fertilizer manufacturer and the names of the brands analyzed. 

 The second column designates the town where each sample was 

 drawn. 



multiply bv 1.216 

 .823 

 .165 



6.071 

 .139 



7.221 

 .258 

 .632 



1.582 

 .541 



1.850 

 .466 



2.146 

 .682 



1.467 

 .458 



2.185 



