Davis.] 170 [Dec. 6, 
decayed. They are as a rule normally rounded on one t^ide, as if 
by water action, and more or less perfectly facetted on the 
other side. They do not necessarily exhibit any systematic asso- 
ciation of internal joints or cleavage with the facets of the 
surface. Moreover, in the case of most of the pebbles, where 
two or more facets have been formed, they have a distinct rela- 
tion to one another, being on oi>e side of the pebble, and all 
slanting towards a common apex. They are almost as systemati- 
cally associated as the roof slopes of a house. If a pebble is 
carved on two sides, the facets as manifestly belong to two 
systems, instead of to only one. 
As to the production of facetted pebbles under water, it would 
certainly be surprising if after all that has been seen and said 
about water action, it would be possible for any of its processes 
to produce edged stones, as sharply cut as those in the gravel 
beds of Cape Cod. Yet it may possibly be worth while to look 
into this matter ; for if pebbles lie on a shoal, across which the 
tide carries sand grains back and forth, may not some kind of 
facetting be the result? If the stone rolls about, it will certainly 
be rounded ; but if it lies still, while the sand passes across it one 
way and another, it is conceivable tliat some facetting might 
result. It is, however, extremely unlikely that this process has 
been effective enough to produce facetted pebbles in such quan- 
tity as they occur on the Cape and elsewhere. 
Neither the splitting by weather and glacial action, nor the 
facetting by water action would account for the known distribu- 
tion of facetted pebbles. Their common occurrence on the 
barren surface of deserts, as described by Walther, and their pre- 
vailing alisence from the till of the later glacial sheets point 
to their origin under wind action. 
Granting this conclusion, it follows that the gravel beds of the 
Cape were accumulated as subaerial deposits ; for it is not to be 
conceived that any process of transportation could fail to round 
off the edges of the pebbles in bringing them, already facetted, 
from some other locality than where they now lie ; or that any 
process of deposition could lay them systematically, edges up, as 
they are so uniformly found. ''This peculiar point regarding their 
occurrence does not seem to have been noted elsewhere in New 
England, but there can be no doubt of its prevalence on the 
Cape. There can consequently be no question that the facets 
