Maurice next spent a few days in reducing the castle of Wouda, not far from Bergen, and then, transporting his army once more to the isle of Cadzand, he established his headquarters at Watervliet, near Ysendyke.  Spinola followed him, having thrown a bridge across the Scheld.  Maurice was disposed to reduce a fort, well called Patience, lying over against the isle of Walcheren.  Spinola took up a position by which he defended the place as with an impenetrable buckler.  A game of skill now began. between these two adepts in the art of war, for already the volunteer had taken rank among the highest professors of the new school.  It was the object of Maurice, who knew himself on the whole outnumbered, to divine his adversary’s intentions.  Spinola was supposed to be aiming at Sluys, at Grave, at Bergen-op-Zoom, possibly even at some more remote city, like Rheinberg, while rumours as to his designs, flying directly from his camp, were as thick as birds in the air.  They were let loose on purpose by the artful Genoese, who all the time had a distinct and definite plan which was not yet suspected.  The dilatoriness of the campaign was exasperating.  It might be thought that the war was to last another half century, from the excessive inertness of both parties.  The armies had all gone into winter quarters in the previous November, Spinola had spent nearly six months in Spain, midsummer had came and gone, and still Maurice was at Watervliet, guessing at his adversary’s first move.  On the whole, he had inclined to suspect a design upon Rheinberg, and had accordingly sent his brother Henry with a detachment to strengthen the garrison of that place.  On the 1st of August however he learned that Spinola had crossed the Meuse and the Rhine, with ten thousand foot and three thousand horse, and that leaving Count Bucquoy with six thousand foot and one thousand five hundred horse in the neighbourhood of the Rhine, to guard a couple of redoubts which had been constructed for a basis at Kaiserswerth, he was marching with all possible despatch towards Friesland and Groningen.

The Catholic general had concealed his design in a masterly manner.  He had detained Maurice in the isle of Cadzand, the States still dreaming of a victorious invasion on their part of obedient Flanders, and the stadholder hesitating to quit his position of inactive observation, lest the moment his back was turned the rapid Spinola might whirl down upon Sluys, that most precious and skilfully acquired possession of the republic, when lo! his formidable antagonist was marching in force upon what the prince well knew to be her most important and least guarded frontier.

On the 8th August the Catholic general was before Olden-zaal which he took in three days, and then advanced to Lingen.  Should that place fall—­and the city was known to be most inadequately garrisoned and supplied—­it would be easy for the foe to reduce Coeworden, and so seize the famous pass over the Bourtanger Morass, march straight to Embden—­then in a state of municipal revolution on account of the chronic feuds between its counts and the population, and therefore an easy prey—­after which all Friesland and Groningen would be at his mercy, and his road open to Holland and Utrecht; in short, into the very bowels of the republic.