PLATE 2. 
Figure 1— Srasonat Banpine In GuaciaAL Ciay at Woopsvitte, N. H. 
Although it may be a mistake to speak of typical seasonal banding, the specimen here shown gives 
an idea of the conditions of seasonal deposition in the glacial clays most commonly seen in the clays 
of the Connecticut Valley and in many other localities. The characters of seasonal banding vary 
according to the conditions of deposition. For at least 1,500 years the widths and general characters 
of the bands show remarkable uniformity. This has been discussed on p. 23. On the seasonal hypo- 
thesis, the relatively small amount of material in the coarse components of the banding, does not appear 
to indicate a long hot summer, but rather a short and moderate summer season. The particles of the 
fine dark component are very small, some of them being not over 1/1000 mm., and the average is 
about 1/600 mm. The particles of the coarse component average about 1/200 mm., with some as 
coarse as 1/12 mm. Some of the sediment in this coarse component is as fine as that found in the 
fine component, but the amount of this fine material is very small. 
Figure 2:— BanpEp SLATE FROM SQUANTUM. 
Specimen of glacial slate from just south of the viaduct connecting Squantum with Moon Island. 
For the purpose of photographing, the dark layers have been slightly darkened to bring out contrast. 
This specimen was exhibited at the Albany meeting of the Geological Society of America in 1916. The 
resemblance of this banding to the banding of the clay specimen above, is striking. Note the homo- 
geneous layers of fine material in comparison with the coarser layers of lighter shade. The changes 
in the conditions of deposition, as shown by the minute stratification in the coarse components, may be 
compared with the similar stratification in the clay specimen above. There were about eight changes 
of conditions, on the average, registered in the slate, while in the clay there is an average of about six. 
Quiet and moving water were responsible for the alternating fine and coarse layers, shown in the coarse 
components. 
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