They show that the diurnal tide at Cape Bryant, Cape Sheridan, Point Aldrich, and Cape Morris Jesup follows that at Fort Conger by respective intervals of 3-1/2, 5, 6, and 8 hours.

They also show that in going northward from Fort Conger to Point Aldrich the ratio of the two principal diurnal constituents approximates more and more nearly to the theoretical ratio; that is, to the ratio between the two corresponding tidal forces.

This is what one would expect to find in passing from a region possessing diurnal tides derived from the irregular tides of Baffin Bay to a region where the equilibrium diurnal tides of the Arctic become important.
The range and time of occurrence of the diurnal tide at Point Aldrich do not differ greatly from their equilibrium values based upon the assumption of a deep polar basin extending from Grant Land and the Arctic Archipelago to the marginal waters off the portion of the coast of Siberia lying east of the New Siberian Islands.

But De Long's party observed tides at Bennett Island in 1881.

From these observations it is seen that the diurnal tide has a much smaller range than would be permissible under the hypothesis of deep water in the portion of the Arctic Basin just referred to.