e and the
latter insoluble in water. The peroxide, however, by the action of
organic matter, such as is held in solution in boggy waters, may be
deprived of a portion of its oxygen and converted into protoxide and
thus be rendered soluble. If the iron-bearing water is confined first in
a shallow basin and exposed long to the action of the atmosphere the
protoxide of iron absorbs the oxygen and is precipitated as an insoluble
red peroxide of iron. If, however, plant or animal life be present in
sufficient quantities, this oxidation is prevented. In case but little
foreign material, clay or sand, has been brought by the waters, the
deposit will be an iron ore. In case large quantities of foreign
material are deposited from the waters at the same time, there will be
produced, in the absence of life, a brown or red clay or sandstone, and
in its presence a white or light colored formation containing the iron
as a carbonate. We reason therefore from the condition in which the iron
is found in the red beds, that there could have been little or no life,
animal or vegetable, in the water from which it was deposited. The
conclusion is strengthened by the fact of the large quantities of gypsum
which are usually derived from the evaporation of saline waters. The
degree of saline concentration which the precipitation of gypsum
indicates, would be highly inimical to life. The presence of gypsum
helps to account for the absence of life, and the absence of life
accounts for the brilliant color. The three prominent characteristics of
the formation (that is the red beds) are therefore quite in harmony with
each other.'" (Geol. Blk. Hills, p. 138.)

Continuing the subject, Professor Todd says: "Accepting this explanation
of the striking red color, the question remains as to how these
circumstances, favorable for its formation, were produced.

"This red color is quite common in the whole Rocky Mountain region, not
only on the eastern slope of the mountains, but to the various detached
members of the system. We must, therefore, look for some extensive
condition. If we seek some case in the present, parallel to the one
already indicated, we perhaps can find none better than one on the
eastern shore of the Caspian Sea, where, because of dry climate and the
shallow waters, the deposition of gypsum and salt is now going on. In
the gulf known as the Kara Boghaz, which is separated from the Caspian
by a narrow strait, the evaporation is so rapid