Following this action, Tromp reappeared with 100 ships, but failed to keep Blake from attacking and ruining the Dutch herring fisheries for that year. This mistake temporarily cost Tromp his command. He was superseded by DeWith, an able man and brave, but no match for Blake. On September 28, 1652, Blake met him off the "Kentish Knock" shoal at the mouth of the Thames. In order to keep the weather gage, which would enable him to attack at close quarters, Blake took the risk of grounding on the shoal. His own ship and a few others did ground for a time, but they served as a guide to the rest. In the ensuing action Blake succeeded in putting the Dutch between two fires and inflicting a severe defeat. Only darkness saved the Dutch from utter destruction. The effect of this victory was to give the English Council of State a false impression of security. In vain Blake urged the upkeep of the fleet. Two months later, November 30, 1652, Tromp, now restored to command, suddenly appeared in the Channel with 80 ships and a convoy behind him. Blake had only 45 and these only partly manned, but he was no man to refuse a challenge and boldly sailed out to meet him. It is said that during the desperate struggle--the "battle of Dungeness"--Blake's flagship, supported by two others, fought for some time with twenty of the Dutch. As Blake had the weather gage and retained it, he was able to draw off finally and save his fleet from destruction. All the ships were badly knocked about and two fell into the hands of the enemy. Blake came back so depressed by his defeat that he offered to resign his command, but the Council of State would not hear of such a thing, handsomely admitted their responsibility for the weakness of the fleet, and set at work to refit. Meanwhile for the next three months the Channel was in Tromp's hands. This is the period when the legend describes him as hoisting a broom to his masthead. By the middle of February the English had reorganized their fleet and Blake took the sea with another famous Roundhead soldier, Monk, as one of his divisional commanders. At this time Tromp lay off Land's End waiting for the Dutch merchant fleet which he expected to convoy to Holland. On the 18th the two forces sighted each other about 15 miles off Portland. Then followed the "Three Days' Battle," or the battle of Portland, one of the most stubbornly contested fights in the war and its turning point.