ADMIRALTY TILL AND CLAYS. i533 
sandy clay of such compactness as to occasion a waterfall. It includes 
many rounded, angular stones, most of them of small size. The Vashon 
till at this point, 200 to 800 feet (60 to 92 meters) above sea, contains con- 
siderable quantities of Hocene coal, probably transported from the out- 
crops near Renton, but none was observed in the Admiralty till. This 
horizon of the Admiralty till is traceable for several miles to the north 
and to the south. 
To the section observed on Carbon river, in which all the principal 
formations have been recognized, the base consists of bluish sandy clay, 
minutely stratified and dipping 15 degrees to the east. The deposit 
includes occasional gravel lenses and passes into fine sand on the top. 
Its altitude is from 460 to 500 feet (140 to 152 meters) above sea. This 
stratified deposit may perhaps be correlated with the Admiralty till, as 
representing a portion of that material which has been redistributed by 
subglacial waters. 
In thus reciting the occurrences of the Admiralty till and clays I have 
followed Russell in correlating them. They are, however, markedly 
diverse in structure, the till having that structureless character peculiar 
to material spread beneath massive ice, whereas the clays are very uni- 
formly and very evenly stratified after the manner of fine material de- 
posited in deep water. The transition from the unstratified to the strat- 
ified masses may indicate the simultaneous occurrence of ice-tongues 
enclosing water bodies of considerable depth. It may be, however, in 
some cases at least, that the stratified and unstratified materials were 
not contemporaneously deposited and should be separated in a logical 
classification. In order to give them distinctive names it appears de- 
‘sirable that the term “till” should be restricted to the unstratified de- 
posits, and the simple term clays be applied to the stratified formations. 
The formations of the Admiralty epoch are so slightly represented in 
the area which I have studied that I do not feel qualified to discuss its 
history. Russell’s observations indicate that the record is not simple, 
and it appears to be possible that more detailed study may show the 
existence of more than one till below the Vashon. The present report 
is to be considered as a preliminary statement only, and all its conclu- 
sions are set forth provisionally and subject to correction by more exten- 
sive field work. : 
SUMMARY 
The Puget Sound basin occupies a geosyncline of Hocene-Miocene 
development between the Cascade and Olympic mountain ranges. 
Within the drift-covered area of the Sound the topographic features fall 
into two classes according to magnitude, namely, (1) major features con- 
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