Prince had his head-quarters at Delft and at Rotterdam. Between those
two cities, an important fortress, called Polderwaert, secured him in the
control of the alluvial quadrangle, watered on two sides by the Yssel and
the Meuse. On the 29th June, the Spaniards, feeling its value, had made
an unsuccessful effort to carry this fort by storm. They had been beaten
off, with the loss of several hundred men, the Prince remaining in
possession of the position, from which alone he could hope to relieve
Leyden. He still held in his hand the keys with which he could unlock the
ocean gates and let the waters in upon the land, and he had long been
convinced that nothing could save the city but to break the dykes. Leyden
was not upon the sea, but he could send the sea to. Leyden, although an
army fit to encounter the besieging force under Valdez could not be
levied. The battle of Mookerheyde had, for the, present, quite settled
the question, of land relief, but it was possible to besiege the
besiegers, with the waves of the ocean. The Spaniards occupied the coast
from the Hague to Vlaardingen, but the dykes along the Meuse and Yssel
were in possession of the Prince. He determined, that these should be
pierced, while, at the same time, the great sluices at Rotterdam,
Schiedam, and Delftshaven should be opened. The damage to the fields,
villages, and growing crops would be enormous, but he felt that no other
course could rescue Leyden, and with it the whole of Holland from
destruction. His clear expositions and impassioned eloquence at last
overcame all resistance. By the middle of July the estates consented to
his plan, and its execution was immediately undertaken. "Better a drowned
land than a lost land," cried the patriots, with enthusiasm, as they
devoted their fertile fields to desolation. The enterprise for restoring
their territory, for a season, to the waves, from which it had been so
patiently rescued, was conducted with as much regularity as if it had
been a profitable undertaking. A capital was formally subscribed, for
which a certain number of bonds were issued, payable at a long date. In
addition to this preliminary fund, a monthly allowance of forty-five
guldens was voted by the estates, until the work should be completed, and
a large sum was contributed by the ladies of the land, who freely
furnished their plate, jewellery, and costly furniture to the furtherance
of the scheme.

Meantime, Valdez, on the 30th July; issue