A century of science in America : $b with special reference to the American Journal of Science, 1818-1918
History
A century of science in America : $b with special reference to the American Journal of Science, 1818-1918
American journal of science; Science -- United States -- History
_Triassic of Atlantic States._—The fresh-water Triassic of the Atlantic
border states was first mentioned by Maclure (1817), who regarded it as
the equivalent of the Old Red Sandstone of Europe. In this he was
followed by Hitchcock in 1823 (=6=, 39), the latter saying that above it
lies “the coal formation,” which is true for Europe, but in America the
coal strata are older than these red beds, now known to be of Triassic
age.
The first one to question this correlation was Alexandre Brongniart, who
had received from Hitchcock rock specimens and a fossil fish which he
erroneously identified with a Permian species, and accordingly referred
the strata to the Permian (=3=, 220, 1821; =6=, 76, pl. 9, figs. 1, 2,
1823). The discerning Professor Finch in 1826 remarked that the red beds
of Connecticut appear to belong “to the new or variegated sandstone,”
because of eight different criteria that he mentions. Of these, but two
are of value in correlation, their “geological position” and the
presence of bones other than fishes. In the Connecticut area, however,
the geological position cannot be determined even to-day, and in Finch’s
time the bones of dinosaurs were unknown. Finch then goes on to point
out the occurrences of Old Red Sandstone in Pennsylvania, but all of the
places he refers to are either younger or older in time. Here we again
see the fatality of trying to make positive correlations on the basis of
lithology and color (=10=, 209, 1826). In 1835, however, Hitchcock
showed that the bones that had been found in 1820 were those of a
saurian, and accordingly referred the strata of the Connecticut valley
to the New Red Sandstone, a term that then covered both the Permian and
the Triassic. In 1842, W. B. Rogers referred the beds to the Jurassic,
on the basis of plants from Virginia. In 1856, W. C. Redfield
(1789–1857), because of the fishes, advocated a Lias, or Jurassic age,
and proposed the name Newark group for all the Triassic deposits of the
Atlantic border. More recently, on the basis of the plants studied by
Newberry, Fontaine, Sturr, and Ward, and the vertebrates described by
Marsh and Lull, the age has been definitely fixed as Upper Triassic (see
Dana’s Manual of Geology, 740, 1895).
_Unearthing of the Paleozoic in North America._
Public-domain text, read in full here on John Shaqi.
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