117
THE CHANNEL OF DRIFT IN THE VALLEY
OF THE CAM.
"On a Deep Channel of Drift in the Valley of the Cam, Essex." By W.
WHITAKER, B.A., F.R.S., F.G.S. Quart. Journ. Geol. Soc, Vol. XLVI.,
PP. 333—40. (May, 1890).
READERS of the Essex Naturalist will remember that a short
paper by Mr. Whitaker, with the above title, appears in Vol. iii.,
pp. 140-2 (1889). The account in the Quart. Journ. Geol. Soc,
besides being fuller in detail generally, is accompanied by an outline
map of Littlebury, on which are the sites of the wells alluded to, and
a section across that village showing the depth of the channel there.
And in it the nature of the channel is discussed. After rejecting the
notions that it may be the result of the existence of a fault, of a local
settlement of the Chalk, or of pipes in it, Mr. Whitaker arrives at the
conclusion that the channel was cut out by "erosion of some sort, the
effect being perhaps strengthened by later dissolution of the Chalk
which might take place more readily here than elsewhere." He adds
that this explanation alone accounts for the peculiar character of the
Drift in the channel; and that the channel itself was formed either in
Pre-glacial or early Glacial times.
Mr. G. Ingold, well-sinker, of Bishop Stortford, is inclined to think
the length of the channel not six, but eleven miles, but this Mr.
Whitaker considers doubtful, though he remarks that future wells
may possibly prove that there may be "a set of long, narrow basins,
instead of one more even and continuous channel."
In the discussion following the reading of the paper, Dr. Evans
noticed the curious fact that the line of the old valley coincided with
that of the existing one : Mr. Clement Reid suggested that perhaps this
Essex depression might not be a river-channel but a lake-basin : and
Mr. Topley remarked that in Northumberland the river Blyth was in
Pre-glacial times a tributary of the Wansbeck, a deep Pre-glacial val-
ley, now filled with Glacial Drift, occurring between them.
T. V. Holmes.