504 
owed their compactness more to the cementing material than to 
heat or pressure. 
On the Paleontological Aspects of the Middle Glacial Formation 
of the East of England, and on their bearing upon the Age of the 
Middle Sands of Lancashire.—Messrs. Searles V. Wood, and F. 
Harmer. The authors gavea list of 65 species of shells obtained 
from the middle glacial sand in the neighbourhood of Yarmouth, 
of which a large proportion, about 20 per cent., are not now 
known to be living, and one of them, 2rycinel/a ovalis, a coral- 
line crag form, being almost generically extinct ; among which 
they had found five or six shells apparently new. The for- 
mation altogether presents a decidedly southern aspect, with 
strong affinities to the crag, only two species (with the exception 
of the new forms) being unknown to the crag beds. On the 
other hand, the middle sand of Lancashire, as at present de- 
scribed, did not appear to have yielded any shell not now to be 
found in the seas of the immediate neighbourhood. They pointed 
out that the mere fact of the middle glacial sands of the east of 
England, and the middle sands of Lancashire being both of them 
underlaid and overlaid by boulder-clay, was altogether incon- 
clusive, and urged that all the evidence we had at present before 
us would relegate the latter to a much more recent position in the 
glacial sequence. They suggested tentatively that the Lanca- 
shire sands might possibly prove to belong to the Hessle series, 
as there seemed to bea close resemblance between the list of 
shells from Kelsey Hill, believed by them to belong to the 
Hessle series, and those from Blackpool. 
In the discussion which followed, Sir Charles Lyell was under- 
stood to say that he was inclined to accept the conclusion of the 
authors. 
Mr. Hughes did not think there were as yet sufficient data to 
correlate the drifts of the East and West of England. But little 
was known of the relations of the drifts of the West to one 
another. We must first trace the included fragments to their 
origin in the mountains, and not form any theory to account for 
the origin and succession of the wide-spread drift of the lower 
country, which will not also account for the phenomena observed 
in the hills. As the result of his own observations, he described 
three drifts occurring in the district north of Liverpool, which 
might be roughly distinguished from one another. 
1. A stiff blue clay with included fragments of the rocks of the 
immediate neighbourhood. This drift occurs at the highest levels 
up to 2,100 feet. The fragments are striated when the rock is 
of such a character as to preserve the scratches, 
2. The ordinary stony clay drift which occurs along the valleys 
and runs up the hill-sides to about 1,800 feet. In the Fv//-cop 
drift, No. 1, the matrix is a very uniform stiff lead-coloured clay, 
no matter what it rests on; while the included fragments may 
have come from rocks about the same level and close at hand. 
In the //i/l-side drift, No. 2, the matrix varies more according 
to the rock on which it rests; while the included fragments, 
which are more numerous than in the F%d/-top drift, No. 1, are 
derived from higher up in the same drainage area ; and, where 
different kinds of rock occur on opposite sides of the valleys, the 
drift on either side is chiefly derived from the rocks on the same 
side, as if it were the lateral moraine of a glacier coming down 
the valley. 
3. In the lower valleys false-bedded sands and gravel, such 
as might be produced by the action of the sea at the end of the 
receding glaciers, overlap the clay drift No. 2, and are almost 
continuous with the great mass of gravel drift which is so largely 
developed on the Jower ground of North Lancashire. But while 
these divisions are tolerably clear in a large way, in deta‘l it is 
difficult to draw a line between them; and when we try to group 
all the drifts in and around the mountain districts of Wales and 
the North of England under one of these heads, or to fit all the 
observed phenomena into any scheme of regular increase and 
decrease of cold—any uniform submergence or elevation, we find 
many exceptions and complications. The false-bedded sands and 
gravels usually occur along the larger valleys at low levels, but 
sometimes we find similar sand gravel dovetailing into the 
boulder clay at various heights; in another place occurring 
along terraces 1,000 feet above sea-level. In the absence of 
organic remains, we cannot yet say which of these should be 
referred to marine action and which to fresh-water streams and 
ponds in and near the melting ice. Flints commonly occur in 
the lower gravels, but once a large unworn flint, about eight 
inches in diameter, was found in the re-sorted surface of the 
highest drift at about 1,900 feet above the sea. In the case of 
the Shap granite boulders, to the mode of distribution of which 
NATURE 
[ Oct. 20, 1870 
Professor Harkness has devoted much attention, the difficulties 
are more obvious, as the rock is so marked. Boulders cannot be 
formed except when the rock from which they are derived is 
above the ice and water. This limits the submergence and depth 
of the ice as to the maximum. But according to the view that 
the boulders were transported over Stainmore into East York- 
shire on floating ice, the south end of the Pennine range must 
have been submerged. This limits the submergence as to mini- 
mum. What was the line of transport of the Shap boulders 
before the submergence of Stainmore? Again, in the drifts on 
the top of Stainmore, we find not only boulders of Shap granite, 
but also fragments of the Permian brecciated conglomerate which 
can have come only from the bottom of the valley more than 
1,000 feet below. Can we believe that these have been lifted by 
shore ice from time to time throughout that long submergence, 
or have we evidence of older drifts of very different origin being 
washed, sifted, and sorted by the encroaching sea. Again we 
find, even on the north side of steep mountain ranges, where we 
should have expected the glaciers to have lingered longest and 
to have ploughed out the old drift, that even boulder-clay has 
travelled up the hill from the lower ground, and must therefore 
be referred to a period when its transport was irrespective of the 
present valleys and mountain slopes. 
In fact, there is much evidence to show that the land ice has 
often ploughed across and transported marine deposits, and the 
sea has often washed and re-sorted the debris brought down by 
land ice, and thus the drift has been used up over and over again. 
That might be the reason why we so often find fragmentary and 
rolled shells associated with perfect though delicate shells, which 
seem to be of the age of the deposit in which they are found. 
He quite agreed with Mr. Searles Wood as to the derivative 
character of some of the shells in the gravel drift recently 
described by Mr. Jamieson, 
But even frequent oscillations of level would not alone be 
sufficient to account for the manner of occurrence of the marine 
drifts, especially when the palzeontological evidence is considered. 
The agencies which produce the warm Western Ocean currents 
must have been in operation throughout the long period under 
notice, but the circumstances which determined the direction of 
those currents must have varied with the changes of level. He 
asked what would be the effect upon the Gulf Stream of a sub- 
mergence or an elevation of a large part of the bed of the Atlantic 
to the amount of 2,000 feet or more? The shells of Moel Tryfaen, 
though of less Arctic character, might well be referred to the 
period of greatest general cold, provided the form of the sea: bed 
and distribution of land turned a warm ocean current on that 
part of the western coast. 
He would, therefore, urge the expediency of adopting the 
method always taught by Professor Sedgwick to his pupils—first, 
to establish clearly the relation of the beds in each separate area, 
and to avoid obscuring an already complicated question by adopt- 
ing prematurely in the West the local nomenclature of the East 
of England. 
On Certain Glacial Phenomena in the Central District of 
Fngland.—Rev. H. W. Crosskey. The author had determined 
the existence of glacial strice in the central plateaux of England, 
and covering these markings on true boulder-clay, physically 
corresponding to the older ‘‘till” of Scotland. The clay with 
granite boulders in the midland counties was of marine origin. 
A succession of drift beds was established from an actual section 
showing a boulder-clay resting on the Bunter sandstone ; second, 
sands and gravels with false bedding ; third, a clay with pebbles ; 
fourth, a bed of sand mixed with clay. 
On some Thermal Springs in the Fens of Cambridgeshire.— 
Mr. F. W. Harmer. In several farm-yard wells near Chatteris, 
of the depth of about ten feet, the author had found water of the 
temperature of 744° Fahr. on the 14th March, the air being but 
37°; and in June of 79}°, the air being then 70°. An analysis of 
the water by Mr. F. Sutton showed that the heat was not due to 
chemical causes. The fens being below the sea-level, and there- 
fore permanently saturated with water at the depth of ten feet, 
and the phenomenon described being apparently continuous over 
an area of ten miles, and no doubt further, the cause producing 
the heat would not be an insignificant one. Mr. Judd, of the 
Ordnance Survey, affirms that the secondary rocks of this neigh- 
bourhvod are extensively faulted, and may thus afford a commu- 
nication with the central heat of the earth. 
On the Matrix of the Gold in the Scottish Gold Fields.—Dr. 
Bryce. The author had found gold in the fragments of granite, 
