eg. 29' the depth was
found to be 825 fathoms, while in latitude 85 deg. 23' it was found to be
only 310 fathoms. This diminution in depth is a fact of considerable
interest in reference to the possible existence of land to the westward.

The three soundings taken between the point of comparatively shallow
water and the Pole failed to reach bottom. The one made within five sea
miles of the Pole proved the depth there to be at least 1500 fathoms.
This is not at variance with the northernmost sounding taken by the
_Fram_, at a point north of Franz Josef Land and in latitude about 85 deg.
20', viz., 1640 fathoms and no bottom.

TIDES.--Tidal observations upon the arctic coasts of Grant Land and
Greenland were carried out under instructions from the Coast and
Geodetic Survey, this Bureau having been ordered by President Roosevelt
through the Secretary of Commerce and Labor to have such work
undertaken.

The object was to secure observations along the northern coasts of Grant
Land and Greenland at a sufficient number of places for determining the
tides in this region; it being the belief that such observations might
throw light upon the possible existence of a "considerable land mass in
the unknown area of the Arctic Ocean."

Systematic tidal and meteorological observations were carried on day and
night at Cape Sheridan, Point Aldrich (near Cape Columbia), Cape Bryant,
Cape Morris Jesup, and Fort Conger--the periods of time covered at these
stations being about 231, 29, 28, 10, and 15 days, respectively.[5]

The tides were observed upon vertical staves or poles held in position
by means of stones placed around them at the bottom of the shallow water
along the coast. At Cape Sheridan, Point Aldrich, and Cape Bryant igloos
were built over the tide staves. These being heated, usually by means of
oil-stoves, the observers were enabled to maintain open well-holes with
comparative ease.

In order to secure fixed data of reference, permanent bench marks were
established on the land, not far from the igloos or tide staves.

The ice-covering of the water nearly obliterated all wind waves which
generally impair the accuracy of staff readings made in open bodies of
water. The measurement of the height upon staff of the surface of the
water, as the surface rose and fell in the well-holes, was carried on
with great precision, a fact which the plottings of the observations
have well brought out. The observations were taken hourly;