96 BULLETIN OF THE ESSEX INSTITUTE. 



Southwestward (27) towards Fall River (24), frontal 

 deposits are traceable in the terrace from that city to 

 Tiverton, and again in the partly submerged sand-plain 

 at Tiverton Bridge (91) on the island of Rhode Island. 

 The deposits along this line are notably stronger and show 

 more signs of ice action as we approach the region of the 

 interlobate moraine on the west shore of Cape Cod Bay. 



The Pr'ovidence-Bridgewater line. — A fairly distinct 

 line of morainal accumulations with outwash plains ex- 

 tends from the narrows, at Providence (42), northeast- 

 ward, throngh Rehoboth (40), Taunton (37), Raynham 

 (36), Bridge water (35), and so to Pembroke (51), in 

 the North River region, joining the Cape Cod Bay lobe 

 near the Coleman's Heights (57) sand-plain which was 

 built at the margin of that lobe. 



The Bridgewater locality exhibits perhaps the most 

 unique of these deposits near Boston. Sprague Hill (50) 

 the site of a water-tower, is the culminating point of this 

 morainal line. The highest point of the mass appears to 

 be the apex of a large cone built at the ice-front. The 

 northern slope of this hill has all the features of the ice- 

 contact, in its steep slope, in the coarseness of the de- 

 tritus, even boulders being occasionally present as in the 

 morainal terrace of Gilbert. From the ice-contact the 

 deposits fall off rapidly southward in long finger-like 

 lobes, ending on a terrace, which appears to mark a 

 water level in the region. The cone above described ap- 

 pears to have been built above water level. Westwards, 

 near the railroad, sand plains occur, with the ice-contact 

 well develo{)ed. 



About one- quarter of a mile north of this ice-contact 

 line there appears, east of the railway track, an area of 

 typical morainal topography and deposits. A few cut- 

 tings show that the till is locally not more than three to 

 four feet thick and that it overlies water-worn drift of 



