154 TALKS ON MANURES. 



COMPOSITION OF CLOVER-SOIL ONCE MOWN FOR HAY, AND 

 AFTERWARDS LEFT FOR SEED. DRIED AT 212 FAHR. 



Organic matter 5.34 



Oxides of iron 6.07 



Alumina 4.51 



Carbonate of lime 7.51 



Magnesia 1.27 



Soluble in hy- 

 drochloric acid. 



Insoluble in acid 



Potash . 



Soda 10 



Chloride of sodium 03 



Phosphoric acid 15 



Sulphuric acid 19 



( Insoluble silicious matter, 73.84. Consisting of : 



Alumina 4.14 



Lime (in a state of silicate) 2.G<) 



Magnesia 68 



Potash 24 



Soda 21 



Silica 65.88 



99.59 



*' The soil, it will be seen, in general character, resembles the pre- 

 ceding sample ; it contains a good deal of potash and phosphoric 

 acid, and may be presumed to be well suited to the growth of 

 clover. It contains more carbonate of lime, and is somewhat 

 lighter than the sample from the part of the field twice mown for 

 hay, and may be termed heavy calcareous clay. 



" An acre of this land, 18 inches deep, weighed, when very nearly 

 dry: 



Lbs. 



Surface, six inches 2.407,900 



Next " 2,444,200 



Third " 2,480,500 



"Or in round numbers, every six inches of soil weighed per 

 acre 2 millions of pounds, which agrees tolerably well with the 

 actual weight per acre of the preceding soil. 



" The amount of phosphoric acid and nitrogen in each six-inch 

 layer was determined separately as before, when the following 

 results were obtained : 



IN DRIED SOIL. 



First Second TJiird 

 sixincfies, sic inches, six iitc/te*. 

 Percentage of phosphoric acid.., .159 .166 .140 



Nitrogen 189 .134 .089 



Equal to ammonia 229 .162 .108 



"An acre, according to these determinations, con tains in the 

 three separate sections : 



