f iron and alumina 13.24
Carbonate of lime 8.82
Magnesia, alkalies, etc. 1.72
Insoluble silicious matter, (chiefly clay) 47.77
-------
100.00
=======
[A] Containing nitrogen .313
Equal to ammonia .380

"The second square yard from the brow of the hill, where the clover was
bad, produced 13 ounces of air-dry, and partially clean roots, or 1.75
tons per acre. On analysis, they were found to have the following
composition:

Clover-Roots, No. 2. (Bad Clover).

Water 55.732
Organic matter[A] 39.408
Mineral matter, (ash) 4.860
-------
100.000
=======
[A] Containing nitrogen .792
Equal to ammonia .901

"The roots on the spot where the clover was very bad, yielded only 31
lbs. of nitrogen per acre, or scarcely one-third of the quantity which
was obtained from the roots where the clover was good.

"The soil from the second square yard, on analysis, was found, when
freed from stones by sifting, to contain in 100 parts:

Composition of Soil, No. 2. (Bad Clover).

Water 17.24
Organic matter[A] 9.64
Oxide of iron and alumina 11.89
Carbonate of lime 14.50
Magnesia, alkalies, etc. 1.53
Insoluble silicious matter 45.20
-------
100.00
=======
2d
determination.
[A] Containing nitrogen .306 .380
Equal to ammonia .370 .470

"Both portions of the clover-soil thus contained about the same
percentage of organic matter, and yielded nearly the same amount of
nitrogen.

"In addition, however, to the nitrogen in the clover-roots, a good deal
of nitrogen, in the shape of root-fibres, decayed leaves, and similar
organic matters, was disseminated throughout the fine soil in whic