COMPAEISON OF MANURES. 



211 



is fair to assume that when a gardener or a farmer bnj'S potash in 

 a commercial fertilizer, with the same degree of solubilit}- and 

 availability for plant food as in ordinary animal manures or other 

 animal waste used for manure, he will have to pay at least five 

 cents a pound for that potash ; for phosphoric acid of like solubility 

 and availability as in these domestic manures he would pay about 

 nine cents a pound, and for nitrogen, sixteen if not eighteen cents ; 

 I take the lower figure to be sure that I am within bounds. 



How do these prices compare with those actuall}- paid for these 

 plant nutrients in such animal or vegetable manures as gardeners 

 or farmers buy? 



Two or three years ago there came to me from a gentleman of 

 this neighborhood a series of questions as to the comparative 

 cheapness of several of these manures. The questions could be 

 answered, at least with approximate satisfaction, since the inquirer 

 was fortunately able to give me the cost per ton, at his own place, 

 of all the materials in question. I had not time to analyze samples 

 of the manures, and for the necessary information as to their com- 

 position I had to refer to the tables giving the average composition 

 of such matters ; if m^' estimates could have been based on actual 

 analyses of the materials, the}' might have been somewhat, but cer- 

 tainly not very, different. 



The results of m}' calculations are set forth in the following 

 table : — 



Kind of Manure. 



Cow manure .... 

 Horse manure . . . 



Night-soil 



Rockweed 



Fish-chum, half dry 

 Hen manure .... 

 Tanners' waste . . 



6.0 

 4.4 

 0.9 

 6.3 



8.4 



