This wheel was under the fore part of the sledge, and, revolving rapidly, its points caught in the ice or frozen snow and propelled the sledge at a good rate of speed.

The wheel could be raised or lowered, so that its points should take more or less hold of the ice, according as circumstances demanded.

In descending a declivity it could be raised entirely, so that the person on the sledge might coast, and it could at any time be brought down hard to act as a brake.
As soon as it was possible to get everything in order, a party of six men, on electric sledges, headed by Mr.Marcy, started southward over the level ice, carrying with them a number of shells, which were placed in a long line, and connected by an electric wire with the Dipsey.

When the party had returned and the shells were exploded, the most sanguine anticipations of Mr.Marcy were realized.

A magnificent canal three miles long lay open to the south.
Now the anchor of the Dipsey was weighed, and our party bade farewell to the polar sea.