PLATE 6. 
Figure 1.— InrrasmasonaL BANDING IN ‘LAY, NEAR Hanover, N. H. 
In favorable localities it is possible to study the changes in deposition that took place during indi- 
vidual years. To undertake such a study some locality must be found where there was a maximum 
of deposition with a minimum of disturbing factors. This view shows such conditions. The exact 
location of the bands shown may be found by comparing Plate 5, fig. 1. About one foot below the 
trowel slightly to the left may be seen a light-colored form pointed downward, some dry clay not removed 
by the trowel in making a fresh surface. The winter layer is nearly covered by the dise and is about 
oneinch thick. The summer layer below is four inches thick. In this summer layer about twenty-one 
minor changes in deposition may be counted, denoting higher and lower water conditions. Whether 
these alternating layers mean cooler and warmer conditions, or wet and dry, it is impossible, in any 
given layer, to say. The winter layers also show differences in deposition in some cases, but as a rule, 
the clay layers of winter are homogeneous, with no evidence of thaws. 
Figure 2.— Aurmrnatine Layers IN THE SLATE BETWEEN Layers oF FINE CONGLOMERATE, 
Seuantum Heap, Mass. 
For the general description of this deposit see Plate 4, fig. 2. 
