"Let us know the danger at once, Mr. Ten Eyck," said Herman Mordaunt, "that
we may decide for the best."

"Why, sir, I am afraid that the rains and the thaw together, have thrown so
much water into the river, all at once, as it might be, as to have raised
the ice and broken it loose, in spots, from the shores. When this happens
_above_, before the ice has disappeared below, it sometimes causes dams to
form, which heap up such a weight as to break the whole plain of ice far
below it, and thus throw cakes over cakes until walls twenty or thirty
feet high are formed. This has not happened _yet_, therefore there is no
immediate danger; but by bending your heads low, you can see that such a
_break_ has just taken place about half a mile below us."

We did as Guert directed, and saw that a mound had arisen across the river
nearer than the distance named by our companion, completely cutting off
retreat by the way we had come. The bank on the west side of the Hudson was
high at the point where we were, and looking intensely at it, I saw by the
manner in which the trees disappeared, the more distant behind those that
were nearer, that we were actually in motion! An involuntary exclamation
caused the whole party to comprehend this startling fact at the same
instant. We were certainly in motion, though very slowly, on the ice of
that swollen river, in the quiet and solitude of a night in which the moon
rather aided in making danger apparent than in assisting us to avoid it!
What was to be done? It was necessary to decide, and that promptly and
intelligently.

We waited for Herman Mordaunt to advise us, but he referred the matter at
once to Guert's greater experience.