Such language was unequivocal, and hostilities were resumed as fiercely as before.  The besieged welcomed them with rapture, and, as usual, made daily the most desperate sallies.  In one outbreak the Harlemers, under cover of a thick fog, marched up to the enemy’s chief battery, and attempted to spike the guns before his face.  They were all slain at the cannon’s mouth, whither patriotism, not vainglory, had led them, and lay dead around the battery, with their hammers and spikes in their hands.  The same spirit was daily manifested.  As the spring advanced; the kine went daily out of the gates to their peaceful pasture, notwithstanding, all the turmoil within and around; nor was it possible for the Spaniards to capture a single one of these creatures, without paying at least a dozen soldiers as its price.  “These citizens,” wrote Don Frederic, “do as much as the best soldiers in the world could do.”

The frost broke up by the end of February.  Count Bossu, who had been building a fleet of small vessels in Amsterdam, soon afterwards succeeded in entering the lake with a few gun-boats, through a breach which he had made in the Overtoom, about half a league from that city.  The possession of the lake was already imperilled.  The Prince, however, had not been idle, and he, too, was soon ready to send his flotilla to the mere.  At the same time, the city of Amsterdam was in almost as hazardous a position as Harlem.  As the one on the lake, so did the other depend upon its dyke for its supplies.  Should that great artificial road which led to Muyden and Utrecht be cut asunder, Amsterdam might be starved as soon as Harlem.  “Since I came into the world,” wrote Alva, “I have never, been in such anxiety.  If they should succeed in cutting off the communication along the dykes, we should have to raise the siege of Harlem, to surrender, hands crossed, or to starve.”  Orange was fully aware of the position of both places, but he was, as usual, sadly deficient in men and means.  He wrote imploringly to his friends in England, in France, in Germany.  He urged his brother Louis to bring a few soldiers, if it were humanly possible.  “The whole country longs for you,” he wrote to Louis, “as if you were the archangel Gabriel.”

The Prince, however, did all that it was possible for man, so hampered, to do.  He was himself, while anxiously writing, hoping, and waiting for supplies of troops from Germany or France, doing his best with such volunteers as he could raise.  He was still established at Sassenheim, on the south of the city, while Sonoy with his slender forces was encamped on the north.  He now sent that general with as large a party as he could muster to attack the Diemerdyk.  His men entrenched themselves as strongly as they could between the Diemer and the Y, at the same time opening the sluices and breaking through the dyke.  During the absence of their commander, who had gone to Edam for reinforcements, they were attacked by a large force from Amsterdam.  A fierce amphibious contest took place, partly in boats, partly on the slippery causeway, partly in the water, resembling in character the frequent combats between the ancient Batavians and Romans during the wars of Civilis.  The patriots were eventually overpowered.