As to the progress over the snow and ice of those who were to lay the lines of shells, that would be easy enough. It had been supposed that it might be necessary for the party to make overland trips, and for this purpose twenty or more electric-motor sledges had been provided. These sledges were far superior to any drawn by dogs or reindeer; each one of them, mounted on broad runners of aluminium, was provided with a small engine, charged at the vessel with electricity enough to last a week, and was propelled by means of a light metal wheel with sharp points upon its outer rim. 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. The great ball buoy, with its tall pole and weathervane, floated proudly over the northern end of the earth's axis. The little telegraph-house was all in order, and made as secure as possible, and under it the Dipsey people made a “cache” of provisions, leaving a note in several languages to show what they had done. “If the whale wants to come ashore to get somethin' to eat and send a message, why, here's his chance!” said Sammy; “but it strikes me that if any human beings ever reach this pole again, they won't come the way we came, and they'll not see this little house, for it won't take many snow-storms--even if they are no worse than some of those we have seen--to cover it up out o' sight.” “I don't believe the slightest good will ever result on account of leaving this instrument here,” said Mr. Gibbs; “but it seemed the right thing to do, and I would not be satisfied to go away and leave the useless end of the cable in these regions. We will set up the highest rod we have by the little house, and then we can do no more.”