t they could hardly go on. The cold
wind was the first disagreeable thing they had met with on the journey.

But the amazing part of it was that the wind came sweeping along with a
loud roar--as if it brought with it the noise of a large mill or
factory, though nothing of the kind was to be found out there on the
ice. They had walked to the west of the big island, Valen; now they
thought they were nearing the north shore. Suddenly the wind began to
blow more and more, while the loud roaring increased so rapidly that
they began to feel uneasy.

All at once it occurred to them that the roar was caused by the foaming
and rushing of the waves breaking against a shore. Even this seemed
improbable, since the lake was still covered with ice.

At all events, they paused and looked about. They noticed far in the
west a white bank which stretched clear across the lake. At first they
thought it was a snowbank alongside a road. Later they realized it was
the foam-capped waves dashing against the ice! They took hold of hands
and ran without saying a word. Open sea lay beyond in the west, and
suddenly the streak of foam appeared to be moving eastward. They
wondered if the ice was going to break all over. What was going to
happen? They felt now that they were in great danger.

All at once it seemed as if the ice under their feet rose--rose and
sank, as if some one from below were pushing it. Presently they heard a
hollow boom, and then there were cracks in the ice all around them. The
children could see how they crept along under the ice-covering.

The next moment all was still, then the rising and sinking began again.
Thereupon the cracks began to widen into crevices through which the
water bubbled up. By and by the crevices became gaps. Soon after that
the ice was divided into large floes.

"Osa," said little Mats, "this must be the breaking up of the ice!"

"Why, so it is, little Mats," said Osa, "but as yet we can get to land.
Run for your life!"

As a matter of fact, the wind and waves had a good deal of work to do
yet to clear the ice from the lake. The hardest part was done when the
ice-cake burst into pieces, but all these pieces must be broken and
hurled against each other, to be crushed, worn down, and dissolved.
There was still a great deal of hard and sound ice left, which formed
large, unbroken surfaces.

The greatest danger for the children lay in the fact that they had no
general view of the ice. They did not