GLACIAL SUCCESSION IN CENTRAL LUNENBURG—PREST. 169 
back it? If we choose the latter as the cause of many of our 
phenomena, we have the following succession of events. They 
are numbered to accord with the supposed corresponding 
deposits in the sections before given :— 
1. General glacial epoch: Nova Scotia covered by a conti- 
nental glacier which masked the country with an enormous 
thickness of glacial debris of northern origin. 
2. Interglacial epoch of considerable length, during which 
the pre-glacial valley of the Lahave was re-excavated to its 
former depth, immense kames formed, and the remaining drift 
oxidized more completely than any recent deposit. As a proof 
of the enormous length of this interglacial epoch, nothing is 
more convincing than the complete oxidization of these under- 
lying deposits compared to the relatively slight change of a like 
nature wrought in ordinary boulder clay of a more recent date. 
The development of the Pithecanthropus erectus, with its 1000 
cubic centimetre skull, is no surprise when such lengthened 
periods are dealt with (pardon this digression.) 
3. A glacial epoch of shorter duration and less intense 
action. This was probably divided into two lesser epochs near 
the southern limit of its extension by a slight recession, and 
thus gave rise to the upper and lower deposits of Blockhouse. 
There was probably a repetition of such recessions and advances, 
until the general ice sheet dwindled to a local ice field and finally 
disappeared, 
4. A local recession at Blockhouse, as mentioned above, 
during which a few beds of clay, sand, and bog iron were 
deposited. 
5. Aslight re-advance of glaciers on courses governed by 
the Jocal surface contour. In its bearing on the deposition of 
the auriferous drift at Blockhouse, this re-advance was adequate 
to a separate glacial epoch, and from a miner’s stand-point will 
have to be treated as such, 
6. Final retreat of glaciers, formation of river terraces 
and general elevation of the country, during which our now 
submarine river channels were excavated. 
