“I suppose I might tell him,” he said to himself.  “But I guess I won’t.  ‘Blessed is he that expecteth nothing,’ The trick might not work.  I’ll wait.”  He turned to where the mechanics were hard at work adjusting the new propeller.

The repairing had gone on for something over two hours.  The water-channel had completely closed.  The Doctor was pacing the ice, lost in reflection.  Like a flash, there came into Dave’s mind a new problem:  would the current be content merely to close the channel, or would the ice soon begin to buckle and pile?  With an uneasy mind, he urged the workmen to hasten, at the same time keeping an eye on the line of ice where the channel had so lately been.

CHAPTER XVII

“So this is the pole”

Many of the disasters which threaten us in this life pass us by.  So it was with the impending disaster of piling ice near the submarine.  It did not pile.

But there remained the problem of getting the submarine through that six-foot roof to the water beneath.  How was it to be done?

The Doctor still paced back and forth, his unrest written in the furrows of his brow.  The jackies, cheerful as ever, worked at their shift of repairing the craft, or, when not at work, played at “duck-on-rock” with chunks of ice.  Once a seal appeared in a water-hole.  Had he not departed promptly, there would have been fried seal steak and roast seal heart for supper.  A lumbering bear, that had evidently never seen a human being before, was not so fortunate.  His pelt was added to the trophies of the expedition, and his meat was ground into rather tough hamburger.

Finally the mechanics announced that the submarine was again in perfect condition.  Now was the time to try Dave’s last trick.  Sending three men to stretch a hundred-fathom cable from the submarine, and to anchor its farther end to a great ice-pan, he dropped below to return at once with a package.  Cautioning the men not to follow him, he walked away seventy-five yards, bent over the center of an ice-pan, seemingly to adjust certain things and put others in order.  This done, he strung a black cord-like affair from his little pile of objects.  He then measured off ten paces, and repeated these operations.  He then lighted a small gasoline torch, and held the tip of the second cord-like affair to it, then raced to the other for the same purpose.  When this was done, he sped away toward his companions.  His actions were quickly understood by the watching crew.  The furrows on the Doctor’s brow had become mere lines.  He was smiling hopefully.  When Dave tripped over an ice boulder there was a cry of alarm, but he was up in a second, and found shelter with his men.  Instinctively everyone ducked.  Then came two roaring explosions in quick succession.  Bits of splintered ice fell around them like hail.  Before the ice fragments had ceased falling, everyone was climbing to the top of the ice-pile.  What they saw caused a shout of joy.  Where the ice-pan had been was a long stretch of black water that slowly widened until it was quite large enough to float the submarine and allow it to submerge.