TRANSACTIONS OF THE SECTIONS. 85 
Professor Phillips. This discovery, in enriching the Permian group of England, 
showed that at the period remarkable in Germany for the eruption of much igneous 
matter, and very great changes, the era was rife in our country in the elaboration of 
one of our richest ores. 
On the part of Professor Harkness and himself, Sir R. I. Murchison concluded 
by stating that one of the main objects was to show that large masses of red sand- 
stones, in Westmoreland and Cumberland, which overlie the magnesian limestone 
or its equivalent, and which, up to this time, have been viewed as New Red Sand- 
stone, must henceforth be classed as Permian; thereby involving a considerable 
change in all pre-existing geological maps. 
On the Chronological Value of the Triassic Rocks of Devonshire. 
By W. Prncetty, F.R.S, 
On the Drift Beds of Mundesley, Norfolk. By Prof. Parties, /.R.S. 
During his surveys of the Yorkshire coast previous to 1829, the attention of the 
author had been specially directed to the succession of the later Ceenozoic deposits, 
and, as a general result, he presented in the first volume of the ‘Geology of Works 
shire,’ published in that year, a series of deposits, the earliest being ossiferous 
gravels below the boulder-clay, the later being gravels and lacustrine deposits, 
also ossiferous, above that clay. In the same year Sir C. Lyell informed him 
of the proofs which he had collected of the “forest-bed” of the Norfolk coast 
being subjacent to the boulder-clay. To meet these facts by a distinct classifica- 
tion, and others of great exactness collected by Prestwich, Austen, Morris, and 
others, the author employed, in 1853 *, the terms “ preglacial” and “ postglacial,” 
in addition to and limiting the term “ glacial,” which had begun to be generally 
used. 
Having examined in the present year the sections on the Norfolk coast, Prof. 
Phillips was able to measure the thicknesses, so as to be convinced that the total 
above the chalk fell short of 400 feet; that, excepting the cases ascertained by 
Mr. King of bivalve shells in their natural position, no facts of importance ap- 
peared which required or even suggested an immensity of time for their occur- 
rence; and that littoral and estuary agitation of water, rather than any consider- 
able movements upward and downward, were indicated as agencies for the pre- 
glacial gravels, sands, loams, and “forest-bed.” The author was strongly im- 
pressed by the want of any real separation between the “ Norfolk” rather than 
“Norwich” Crag and the other laminated shelly deposits which are subjacent to 
the boulder-clay. The organic remains appear to be not at all opposed to this 
view ; and by adopting one general title for all these beds, immediately above the 
chalk, in the Norfolk and Yorkshire sections, and treating them as deposits of one 
varied series of local effects, with but slight changes of level, there is reason to 
think that a wider basis may be obtained for reasoning on the physical conditions of 
the “ Preglacial ” period. 
On the Deposit of the Gravel, Sand, and Loam with Flint Implements at 
St. Acheul. By Prof. Puirups, PAS, 
A recent visit paid by the author to the gravels of the Somme valley had led 
him to believe that insufficient notice had been taken, in the scheme drawn out 
to determine their age, of those phenomena of river action which would tend to 
change the relative positions of the gravel-layers, and that the general lay or posi- 
tion of the beds composing the deposit had not been enough allowed for in reason- 
ing on the agencies concerned. ‘The materials of the deposit were such as could 
be best accounted for by supposing inundations from melting snows or heavy rains 
on an uncultivated surface like that of the adjoining hills,—rounded pebbles and 
hard sandstones from the tertiary beds; rough flints from the chalk; sands and 
loams, with small flint chippings, from the general surface. The small land and 
freshwater shells associated with the sands above and mixed with the gravel, 
* ¢ Rivers, Mountains, and Sea-coast of Yorkshire,’ 
