. Bulletin of the Essex Institute. Essex Institute; Natural history; genealogy. 100 BULLETIN OF THE ESSEX INSTITUTE. that the observations of Russell on the Malaspina glacier fountains may afford an explanation of this case, for if the subglacial drainage found its way to the surface of the margin of the ice through a crevasse or hole when the lower end of the subglacial streamway became clogged, a break in the continuity of the esker-fan and the esker would be expected. The JVewtonvtlle- Woodland wash-jilains.—The Newton- ville esker-fan described by Professor Davis and modelled by Dr. Gulliv
. Bulletin of the Essex Institute. Essex Institute; Natural history; genealogy. 100 BULLETIN OF THE ESSEX INSTITUTE. that the observations of Russell on the Malaspina glacier fountains may afford an explanation of this case, for if the subglacial drainage found its way to the surface of the margin of the ice through a crevasse or hole when the lower end of the subglacial streamway became clogged, a break in the continuity of the esker-fan and the esker would be expected. The JVewtonvtlle- Woodland wash-jilains.—The Newton- ville esker-fan described by Professor Davis and modelled by Dr. Gulliver lies south of the Charles River apparently in line with larger wash-plains lying between Woodland and Waban stations on the west. The Woodland plains are com- plex in structure, showing the phe- nomena of ice-retreat and the over- lapping of newer plains on those previously laid down. Southeast of Waban station stands a ridoe of gravel and sand with an ice-contact slope on its northwestern face with typical coarse detritus in the contact zone. The opposite side of the ridge is lower, slightly lobate, and the detritus finer. The inclined surface of the deposit suggests that we have in this case an alluvial cone built at the ice edge. The deposit is lengthened parallel with the ice contact. The Cambridge moraine and plain.—Old Cambridge lies upon a plain of sand whose northern limit is a well defined ridge extending from Porter's Station southwest- wards by the Harvard Observatory and thence westwards along the southern border of Fresh Pond to the Water- town line. This ridge rises at three points to the uniform height Fig. 5. The Mechanics- ville wash-plain with the esker-like deposit north of it. The " notch " between the esker and the plain is followed by a stream and is occupied by a pond. (Topography from Frank- lin atlas sheet, U. S. Geol. Survey.). Please note that these images are extracted from scanned page images that may have been digitally enhanced fo
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