268 Reviews—Howse on Glaciation in N. Britain. 
subject of time. It is one that needs all the care and caution of the 
sage, as well as the boldness and vigour of a fresh intellect. 
The Address of Dr. Dawson is also chiefly devoted to the subject 
of Boulder-drift, and the conditions of its deposit in Canada ; but it 
does not relate to the vexed question of the Antiquity of Man. Dr. 
Dawson urges the extreme improbability that, under any conceivable 
physical conditions, there should have been land-glaciers sufficient to 
account for the phenomena of Boulder-drift in Canada. 
GLACIAL ACTION IN NORTHUMBERLAND AND DURHAM. 
N interesting paper on the Glaciation of the Counties of Dur- 
ham and Northumberland, by Mr. R. Howse, has recently 
appeared in the ‘Proceedings of the North of England Institute of 
Mining Engineers’ (May 1864). In it the author observes that fine 
examples of glaciated rock-surface have been brought to light in 
baring the Magnesian Limestone for quarrying near South Shields. 
In other localities the surface of this limestone has also been found 
more or less polished and scored. The harder sandstones also of the 
Coal-measures, and the Mountain-limestone, which crop out to the 
north and west of the former rock, both show the same phenomena. 
The direction of the grooves and scratches varies in different loca- 
lities, and even in the same locality ; it being sometimes to the N., 
sometimes to NE., and sometimes due E., within an area of a few 
acres. Resting on glaciated as well as on non-glaciated rock-surfaces 
is a deposit of brown, reddish, grey, or bluish clay, full of rock- 
fragments, varying in size from the smallest grain to blocks of five 
and six tons weight. Some are angular, but most of them are more 
or less worn. Many, both large and small, are very much glaciated ; 
and some are not unfrequently scratched and ground in different 
directions on their different surfaces, and sometimes on the same 
surface ; it is indeed the exception to meet with glaciated fragments 
scored and scratched in straight and parallel lines. 
The materials compesing the deposit—both clay and boulders— 
are largely composed of the rocks on which it immediately rests, or 
which underlie it to the west. ‘Thus, in the north-eastern district 
of Durham, where Mr. Howse seems to have pursued his investiga- 
tions in most detail, the deposit is chiefly composed of débris from 
the Coal-measures and Magnesian Limestone; the remainder has 
come from the Millstone-grit, Mountain-limestone (including the 
associated basalts), Old Red conglomerate, the porphyry of Cheviot, 
and the granites of Criffle and Shap-fell. The deposit is pretty 
generally distributed over the district; but is thickest towards the 
sea-board and in the valleys. Where thickest, it is 60, 100, and 
sometimes nearly 150 feet; but from 20 to 50 feet is its most usual 
thickness. It usually shows no trace of stratification, the materials 
having been thrown together without the least assortment; but fre- 
quently a more regular structural arrangement obtains. Until re- 
cently it was supposed to be devoid of fossils; fragments of Cyprina 
Islandica, have, however, lately been found in it. 
Above this Boulder-clay either resting on it, or forming its upper- 
