282 Chronicles of Science. [ April, 
them having fallen previously to the last emergence of the land, that 
ram is incapable of abrading hard rocks, and that it would be 
difficult to exaggerate the denuding power of the sea as a laterally 
operating and undermining agent. Much might be said for and 
against these assertions; but we will merely remark that Mr. 
Mackintosh seems unable to imagine that the action of surface- 
currents and waves would tend to plane down the surface of a 
gradually rising mass of land; indeed, the possibility of the bed of 
a sea or ocean ever having been subjected to such an action does not 
seem to have occurred to him, for he states that the assumption of 
“the subaérialists” that the sea tends to plane down the land “is at 
variance with the generally received principle of physical geography, 
that the bottom of the sea at any given time is as uneven as the dry 
land.” If the upheaval of sea and ocean beds were always violent 
and sudden, Mr. Mackintosh would no doubt be right. Mr. Searles 
Wood’s paper contains the enunciation of some important views and 
statements; but we must postpone their consideration until after 
the completion of the paper. 
PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 
Tue very small number of the Society’s journal that we have this 
quarter to notice, contains three or four papers of average impor- 
tance. Mr. Godwin-Austen’s paper ‘On the Submerged Forest- 
beds of Porlock-bay’ possesses, perhaps, the greatest interest for 
the English geologist, as the evidences of geological changes which 
these beds present are much more complete than those exhibited by 
the similar deposits in Bridgwater and Swansea bays; “ besides 
which, they better serve to illustrate the nature and order of oscilla- 
tions of small amount, which have taken place at times shortly ante- 
cedent to the present.” The chronological sequence, and the nature 
of the deposits, are in descending order as follows :—(1) Shingle 
bank, (2) Marine silt, (3) Surface of plant-growth, (4) Fresh- 
water mud-deposit, (5) Forest-growth, (6) Angular detritus. 
Collatng Mr. Godwin-Austen’s reading of the evidence, we have 
the following history of the more recent geological changes which 
have occurred in this neighbourhood. The Angular Detritus (6) 
was formed, when the land was at its highest relative level, by sub- 
aérial weathering of the rocks on the high ground, and the accu- 
mulation of the débris at lower levels during the Glacial Period, 
and contemporaneously with the deposition of the Boulder-clay in 
the more northern parts of Britain. On this detrital accumulation 
forest-trees grew, and attained a great age; the trees were then 
killed by the deposition of freshwater mud,—the result, probably, 
of a depression of the land. Water-plants grew on the nearly dry 
surface of this mud-deposit, on which the trees fell, and the land 
