AREAL DESCRIPTION 629 



had been subjected only to atmospheric agents, yet destitute of drift, 

 may be regarded as having been wave-swept; and surely so if they fall 

 beneath the level of the marine plane. For example, the highest points 

 on the road from Seal Harbor to Bar Harbor are the crossings of two 

 rock ridges with altitudes of 240 feet by the map. The granite ledges 

 here are entirely bare. The ice-sheet must have rubbed some drift into 

 the hollows or dropped it in the lee of ledges. Storm water could rinsa 

 off the finer stuff and leave some coarser as talus, but these ledges have 

 nothing which heavy waves could joggle off. 



With reference to the constructional effects of submergence — the de- 

 posits — we may postulate the following, based on the mechanical con- 

 ditions : 



(1) Sui)glacial till, left only in protected places. 



(2) Kames or glacio-aqueous deposits at the higher levels of the sea. 



(3) Unassorted gravel and sand at inferior levels, a homogeneity ot 

 heterogeneity or pell-mell structure. 



(4) Deltas or stratified deposits, of glacial outwash only at the sum- 

 mit marine level and of land drainage at the summit level and all in- 

 ferior levels. 



(5) Silt or clay in sheltered places of deeper water and now at lower 

 levels. 



(6) Sands over silts and on other surfaces protected from the rinsing 

 work of waves during the land uplifting. 



(7) Possible veneer of gravel in places where wave-work on the rising 

 land was competent to distribute materials, but not to wholly remove 

 them. 



(8) Wave-swept bare rocks at all levels beneath the marine summit. 

 Exposures of number 1, true till, are found in road cuttings. This 



is the subglacial drift which was left either in deep water or in sheltered 

 places. The englacial and superglacial drift was dumped from the ice- 

 front or carried out by the drainage to produce number 3 in the deeper 

 waters or number 4 in shallow water. The rock flour, or fine suspended 

 material, was swept out, some of it being left as number 5. The most 

 common deposits are the pell-mell gravels, number 3. Exploration was 

 not carried far enough to identify number 2. The more evident and 

 unequivocal proof of the standing water is number 4. 



Evidence of submergence was first sought, not on rock slopes and 

 exposed headlands, but in the sheltered valleys, and an excellent outwash 

 plain was found close to Seal Harbor. Passing north up the road toward 

 Jordan Pond, bedded sands are found from sealevel up to 200 feet. A 



