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; and during a large percentage of the time these were supplemented by observations taken more frequently, often at intervals of ten minutes each.
The chronometer used in connection with tidal work was compared with true Greenwich time at New York before and after the cruise to the Arctic.