a 
wt 
* 
bi ee. often form long and narrow hills, running ea rth-east, some 
120 Scientific Intelligence. 
; obliterated since the glacial epoch. The trap — near Edin- 
, of them 800 feet high, and several of them sored li ffs to the west, — 
“and long gentle — on the east. Mr. Chambers described the — 
Costorphine Hill as a stratum of trap dipping to the west, and with a 
cliff in a line north eae south. In its crest, which rises to 470 feet 
above the sea, are three or four transverse clefts: On the west surface 
of the hill, the rock, wherever it is exposed, is found to be rounded 
(moutonnée), smoothed, and grooved. ‘The grooves, and the clefts in 
the crest of the hill, all lie in one direction, viz., directed to a point to 
the north of east. There are also, to the east oF the hill, long hollows, 
with rounded intervening swells ; and these run in precisely the same 
direction. At various places between the hill and the sea are seen 
sandstone surfaces, worn down toa remarkable flatness and smooth- 
ness, and in several instances marked with strie, all pointing in the 
same direction. In Edinburgh itself, the north side of the Castle rock 
is smoothed and horizontally grooved, as if by ice passing along the 
hollow below. In forming the Queen’s drive, on the south side of 
Arthur’s =e the surface of the rock in te hollow between that hill 
and ** Sampson’s Ribs,” was found to be wholly smoothed, polished and 
eat UF striated in the direction of the passage, which is easterly ; 
on the north side of the same hill, the railway works have also laid bare 
ro 
400 feet.. Throughout the Valley of the Forth, from the Pentlands on 
one side to the Fife hills on the other, from Linlithgow to Dunbar, the 
sandstone surfaces, wherever the me are likewise smoothed, 
existing glaciers produce. ut there was great room for specula- 
tion as to the circumstances under which the presumed glacial agent 
erican continent, in a direction admitted to be tolerably pian 
forth. ce ; this ico: wes ae “of aiaiiliog aes 
tains of ‘da eae height. : v, v 
of the Forth, there co uld be an ice-torrent of undeviati 
