d masses extending over a considerable portion of the
unknown region of the Arctic Ocean.

No further attempt will be made here to prove the necessity for a tract
of land, an archipelago, or an area of very shallow water situated
between the present Arctic Archipelago and Siberia. A brief discussion
of this question, together with a tidal map of the Arctic Regions, will
be found in a paper about to be issued by the Coast and Geodetic Survey
and which has been already referred to. A few pertinent facts may,
however, be mentioned.

(1) At Point Barrow, Alaska, the flood stream comes from the west and
not from the north, as the hypothesis of an extensive, deep polar basin
implies.

(2) The semidaily range of tide at Bennett Island is 2.5 feet, while it
is only 0.4 foot at Point Barrow and 0.5 foot at Flaxman Island, Alaska.
This indicates that obstructing land masses lie between the deep basin
or channel traversed by the _Fram_ and the northern coast of Alaska.

(3) The observed tidal hours and ranges of tide show that the semidaily
tide is not propagated from the Greenland Sea to the Alaskan coast
directly across a deep and uninterrupted polar basin.

(4) The observed ranges of the diurnal tides at Teplitz Bay, Franz Josef
Land; at Pitlekaj, northeastern Siberia; and at Point Barrow and Flaxman
Island have less than one-half of their theoretical equilibrium values
based upon the assumption of an uninterrupted and deep polar basin.

In addition to these facts are the following items which have a bearing
upon the shape and size of this unknown land:

The westerly drifting of the _Jeannette_.

The westerly drifting north of Alaska observed by Mikkelsen and
Leffingwell.

The existence of Crocker Land.

The shoaling indicated by a sounding of 310 fathoms taken in Lat. 85 deg.
23' N.

The eastward progression of the tide wave along the northern coast of
Grant Land as shown by observations at Point Aldrich, Cape Sheridan, and
Cape Bryant.

The great age of the ice found in Beaufort Sea.

Items of some importance in this connection, but which cannot be
regarded as established facts are:

The probable westerly courses taken by casks set adrift off Point Barrow
and off Cape Bathurst, the one recovered on the northeastern coast of
Iceland, the other on the northern coast of Norway;

The question suggested by Harrison whether or not enough ice escapes
from the Arctic to account for the quantity which must be formed