from the excavation as he heard it and reach the side of Oak as the
latter came literally tumbling down the bole of the tree of watching.

"Run!" Oak said, and the two darted across the valley and reached the
forest and clambered into safe hiding among the clustering branches.
Then, in the intervals between his gasping breath, Oak managed to again
articulate a word:

"Look!" he said.

Ab looked and, in an instant, realized how wise had been Oak's alarming
cry and how well it was for them that they were so distant from the clump
of trees so near the river. What he saw was that which would have made
the boys' fathers flee as swiftly had they been in their children's
place. Yet what Ab looked upon was only a waving, in sinuous regularity,
of the rushes between the tree clump and the river and the lifting of a
head some ten or fifteen feet above the reed-tops. What had so alarmed
the boys was what would have disturbed a whole tribe of their kinsmen,
even though they had chanced to be assembled, armed to the teeth with
such weapons as they then possessed. What they saw was not of the common.
Very rarely indeed, along the Thames, had occurred such an invasion. The
father of Oak had never seen the thing at all, and the father of Ab had
seen it but once, and that many years before. It was the great serpent of
the seas!

Safely concealed in the branches of a tree overlooking the little valley,
the boys soon recovered their normal breathing capacity and were able to
converse again. Not more than a couple of minutes, at the utmost, had
passed between their departure from their place of labor and their
establishment in this same tree. The creature which had so alarmed them