feature of the Gulf of Maine, upon which I am here insisting, 

 viz., its nearly continuous eastern rim; which, though no less 

 real than the western border of the gulf, escapes recognition 

 through its submergence beneath the waters of* the Atlantic. 

 One of the most important eiFects of glacial action was the 

 transportation of immense quantities of detrital materials from 

 the north and north-west toward the south and south-east. 

 According to Prof. Hitchcock, the sheet of drift covering 

 South-eastern Massachusetts is at least three hundred feet 

 thick ; and any one familiar with the geology of this region, 

 who notes the characters of the pebbles and boulders which 

 this drift contains, cannot doubt that it has been largely 

 derived from the land to the northward ; nor will it seem 

 improbable that Northern Massachusetts, and even New Hamp- 

 shire, may have contributed something to the result. We have 

 no reason to think the action of the ice-cap in this instance 

 was anything exceptional ; it probably swept Northern as well 

 as Southern New England, and in even a more thorough 

 manner. Where now is the vast accumulation of debris that, 

 according to this supposition, must have been removed from 

 portions of Maine and New Hampshire ? I believe it has been 

 shoved, in large part, beyond the present limits of the land, 

 and is now spread over the bottom of the Gulf of Maine ; 

 contributing largely to the elevation of this bottom to the level 

 of the eastern rim, and thereby tending to obliterate the latter 

 as such. Jeffrey's Bank and Cashe's Ledge, lying off the 

 mouths of the Kennebec and Penobscot Rivers, sixty to seventy 

 miles long, two-thirds as broad, rising from a depth of one 

 hundred and sixty fathoms, and approaching at many points 

 within live to fifty fathoms of the surface, should, apparently, 

 be regarded as a huge pile of glacial detritus, which, although 

 everywhere distinct from the eastern rim of the gulf, greatly 

 obscures its basin-like character. That the glacial action, 

 while tending to fill up the gulf, has contributed little or 

 nothing to the formation of the ridge or plateau constituting 

 its eastern border becomes sufficiently obvious when we note 



