'Transactions of the Bombay Geographical Society, from September 1850 to June 1852. Edited by the Secretary. Volume X.' [‎222] (355/458)

:222 notes.
farther similar to those of chalk flint in the manner in which the loose pieces ap e
imbedded in the clay, and in the layers being composed of detached pieces
-Now it appears some presump ion against the whole of these vast collections of
nodules being due to calcareous springs, that recent though their formation has
been proved to be, there are no independent indications of the existence of the
■springs whence they could have been derived. So universal is the prevalence of
kunkur, that it is scarcely possible to believe the whole traces of its originating
sources have been obliterated. Farther, from the appearances of the beds with
which the kunkar is associated, it is evident that no springs have been in action
since they were deposited, and the nodules must consequently have been brought
from a distance* There is some difficulty however in accounting for the occurrence
of beds 4 feet thick, with no intermixture of foreign substances, but consisting
entirely of nodular limestone, on this supposition. Detritus of such an orign is
'invariably mixed, and contains specimens of the different material which the
force of the transporting agent was capable of bearing along. The shooting of
brandies and the gradual passing of the kunkur into the clay above and below,
seem farther to militate against the idea of the operation of powerful, or even
any transporting agency An office of the East India Company and, later, of the British Raj, headed by an agent. . It has been said that the kunkur of India has no
analogous formation in the world; but I conceive this to be doubtful, as it is
known that the [London clay 2 * contains numerous contemporaneous nodules of
hard marel or clayey limestone, which occur in regular horizontal layers at une*
qual distances, usually varying from four to forty feet apart. Tliese nodules are
called Sept aria, from their being divided by partitions or veins of calcareous spar,
and in their cavities are frequently found crystals of calcareous spar (carbonate of
lime) and heavy spar (sulphate of baryta.) The Septaria are surrounded by
ciusts which contain a smaller proportion of lime than the central parts; and of the
GHiazipoor kunkur, Mr. Everest remarks similarly that its cavities are lined with
ciystals, and that while the fresh fracture is of a brownish grey colur, exhibiting
the stone compact, the exterior is covered with a white or yellowish white crust.
The chemical composition of the Septaria of the London clay is identical with
that of the Ghazipoor kunkur, consisting chiefly of carbonate of lime with silica,
alumina and oxide of iron, or slightly ferruginous clay, and the natural cement
stones of Harwich, Sheppy, and other places, are used for the same purposes in
England as the kunkurs are in India, f In the tertiary basin of Paris similar tu*
beiose masses are found in the clayey and calcareous marl of the Afth and sixth
formations.! It is scarcely necessary to remark, that I do not mean to contend that
the Indian kuukurs are contemporaneous with the similar concretions of tho tertiary
formations of England and France, I only wish to exhibit the analogy existing
etween them, as this may help us to some explanation of their origin. The analogy
might be extended to several other members of tertiary formations, as the strata
#
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jntlie clayey
observe!
W3
ib we possess c
of them pe
UijiM their fin
itifolly preserv
ytliey were quietl
Wfently no tran
giated masses of 1
llieve the flint coi
lit is imbedded, an
Mules of the
tr, there is thus ai
riiathe places wh
irfrom silicic
ir the flints'
^ of the Paris b
IJ K(says Prof
or 'g'n of the
presen
08 to infer thi
h^ier limestone
lo,ll) t from the
similar
“’and the
k | e( j t
i the
7 arc
• Cuvier’s Theory of the Earth.
T Easley on Cements, and Note C
t Cuvier's Theory of the Earth, °