d of its column from the neighbouring village were not traversed by its
last units, nor was the whole body drawn up at the foot of the hills
against the water until the sun of that late August day was beginning to
rise, and to show more clearly the great sheet of flood-water and the
steep distant bank beyond it.

The place to which their guide had led them was the entry to the ford of
Blanchetaque, a name famous in the military history of this country.
Hidden beneath the waters which, though now ebbing strongly, were still
far too deep for any attempt at a crossing, ran the causeway. By it, upon
the faith of the traitor, they could trust to gaining the opposite shore.
As the racing ebb lowered more and more, the landward approaches of that
causeway appeared in a lengthening white belt pointing right across
towards the further bank, and assured them that they had not been
betrayed. It was built of firm marl in the midst of that grassy slime
which marks the edges of the Somme valley, and they had but to wait for
low water to be certain that they could make the passage. Beyond, upon the
northern shore which showed in a high, black band (for it was steep)
against the broadening day, they could distinguish a force that had been
gathered to oppose them.

It was mid-morning before the ebb was at its lowest,[9] and they could
begin to march "twelve abreast, and with the water no more than
knee-high," across the dwindled stream now at its lowermost of slack
water, and running near the further bank with a breadth not a fifth of
what it had been at the flood. But before proceeding further and
describing the assault shore, I would lay before my readers the process by
which I have established the exact locality of this famous ford. It has
been a matter of considerable historical debate. It is and will always
remain a matter of high historical interest, and this must be my excuse
for digressing upon the evidence which, I think it will be admitted,
finally establishes the exact trajectory of Blanchetaque.

The site of Blanchetaque is one which nature and art have combined to
render obscure: nature, because a ford when its purpose disappears and it
is no longer kept up, that is, an artificial ford, tends to disappear more
rapidly than any other monument; art, because the old estuary of the Somme
has of recent years been further and further reclaimed. It was, when I
first began studying this district, already banked across below Boismo