Shaler.] 278 [May 7, 
NotTEs ON THE SUBMARINE COAST-SHELF, OR HUNDRED FATHOM 
DeETRITAL Friner. By N. S. SHALER. 
I have been for sometime engaged in an inquiry into the nature, dis- 
tribution and effects of the one hundred fathom detrital fringe which 
borders all the tide-swept shores of the North Atlantic, and probably 
those of other oceans. A thoroughgoing inquiry into the history of 
this singular structure presents so many difficulties, that it may be 
many years before I find myself in a position to come to any final 
conclusions concerning its problems, and therefore, venture to give 
a brief synopsis of the conclusions to which I find myself drawn by 
the evidence now in my possession. 
In the first place it is to be noted that this deposit, which I shall 
for convenience, term the coast-shelf, exists along the whole coast of 
the North Atlantic Ocean, and that while it differs very much indeed 
in width, and consequently in mass as well, its slopes show a singular 
likeness in all the sections. In the next place we should notice, 
that this shelf has been formed with a very great uniformity along 
shores which have had a very great diversity in their history, 
and exists along shores which have recently been subjected to great 
elevations, as well as along others which have been for a long time 
nearly stationary, and also along yet other shores which have been 
undergoing considerable subsidence in the last geological period. For 
instance, on the North American Atlantic sea-coast we find it about 
the Labrador coast where the shore has very recently beensubjected 
to an elevation of over one hundred fathoms, again on the coast near 
Cape Hatteras, where the change in the same time has been very lit- 
tle, and yet again off the South Carolina coast, we have the same 
fringe of detrital matter, though that region has recently subsided a 
good deal. 
From such facts we are driven to the conclusion that this shelf is 
rapidly formed, and that itmay be accumulated in either of the three 
conditions of upheaval, subsidence, or immobility of the shore. I 
am inclined to the opinion, however, that while the shelf may be 
formed in either of these three diverse conditions, its formation is 
much favored by the first of these, 7. e., the process of upheaval. 
The next most important fact connected with this deposit, is its 
apparent absence or change of character along the shores of the 
tideless seas. So farI have been unable to find any distinct indi- 
