HISTORY OF THE AMERICx\N MENHADEN. 237 



The following rates of valuation were adopted by Professor Goess- 

 mann in 1871-75 and 1875-'7G : 



1674-'75. 187ri-'76. 



Por pouDtl. Pit pound. 



Soluble phosphoric acid Ifi. 25 cents. 12. 5 cents. 



Reduced i:j cents. 10 cents. 



Insoluble phosphoric acid iu mineral phosphates 5 cents. 4 cents. 



Insoluble i)hoKphoric acid in bones, lish, and animal dust G cents. G cents. 



Nitrogen 30 cents. 25 cents. 



Potassium oxide in muriate 8 cents. 6 cents. 



Potassium oxide in sulphate 8 cents. 8 cents. 



Professor Johnson, in tbe report of the Connecticut station for 1877, 

 says as follows : 



''The following are the trade-vahies or cost in market, per pound, of 

 the ordinarily occurring forms of nitrogen, phosphoric acid, and potash, 

 as recently found in the New York and New England markets: 



Cents per pound. 



Nitrogen in ammonia and nitrates 24 



Nitrogen in Peruvian guauo, fine steamed bone, dried and fine-ground blood, 



meat, and fish 20 



Nitrogen in fine-ground bone, horn, and wool dust 18 



Nitrogen in coarse bone, horn shavings, and fish scrap 15 



Phosphoric acid soluble in water 12^ 



Phosphoric acid ' reverted ' and in Peruvian guano 9 



Phosphoric acid, insoluble, in fine bone and fish guano 7 



Phosphoric acid, insoluble, in coarse bone, bone ash, and bone-black 5 



Phosphoric acid, insoluble, in fine ground rock phosphate 3^^ 



Potash in high-grade sulphate 9 



Potash in kaiuit as sulphate 7J 



Potash in muriate or potassium chloride 9 



" These ' estimated values' are not fixed, but vary with the state of 

 the market, and are from time to time subject to revision. They are not 

 exact to the cent or its fractions, because the same article sells cheaper 

 at commercial or manufacturing centers than in country towns, cheaper 

 in large lots than in small, cheaper for cash than on time. These values 

 are high enough to do no injustice to the dealer, and accurate enough to 

 serve the object of the consumer. * * * The 'estimated values per 

 pound' in the above schedule are similar to those employed by Dr. 

 Goessmanu and Professor Atwater in their recent reports." 



This method of estimating the commercial values of fertilizers has 

 been long practiced and has its uses, particularly as a forcible means of 

 illustrating frauds, and as the first step in the process of educating farm- 

 ers and manufacturers. People who' are not familiar with chemical 

 terms understand dollars and cents, and are much more impressed by a 

 fertilizers " analyzing" $30 per ton when the price is $15, than by its 

 containing only six per cent, of soluble phosphoric acid when it ought to 

 have twelve. 



These calculations are, however, open to serious objections, with the 

 rest, because they not only differ very widely from the agricultural 



