in (A) 1-1.7, in (B) 1-2.8, a proof that the Silicates, which were
washed out during degradation, contained more silicic acid as the
degradation advanced.

Not long ago, Ebleman* made experiments to investigate the
changes which the Basalt undergoes from Lintz on the Rhine.—
This Basalt was also disjoined by degradation into globulous and
concentric masses around a centre mass of black gray color, which
had not yet been attacked by water and atmospheriles. The
analyses of them gave the following result:

Silica,

†Titanic Acid,
Clay,

Peroxyd of Manganese,
Protoxyd of Iron,
Magnesia,
Lime,
Soda,
Potash,
Water,

100.2                         100.6

Or, calculated for 100 parts of clay:

Fresh.	Disintegrated
45.9	43.2
1.0	1.2
16.2	18.9
0.3	0.3
13.0	14.6
6.3	5.6
10.3	8.2
3.6	1.4
1.2	0.5
2.4	6.7

Silica,	283	228
Titanic Acid,	6	6
Clay,	100	100
Protoxyd of Iron, Peroxyd of Manganese,	} 80	78
Magnesia,	39	29
Lime,	63	43
Soda,	22.2	7.4
Potash,	7.4	2.6
Water,	15	35

Hence it follows that during degradation the following quanti-
ties were washed out:

D

Oxygen.

28.6
0.4
5.7

3.9 14.5
0.8
3.7

*Ann. des Mines, iv. Ser. T. xii., p. 637.          † Non-essential to vegetation.

Silica,	55
Protoxyd of Iron,	2
Lime,	20
Magnesia,	10
Potash,	4.8
Soda.	14.6

37