Cromwell saw the fatal mistake which had been committed, and in the night moved round his troops to his left, and these at daybreak fell upon the Scottish right. The night had been wet, and the Scottish army were unprovided with tents. Many of their matchlocks had been rendered useless. At daybreak on the morning of the 3d of September the English, led by General Lambert, fell upon them. The Scotch for a time stood their ground firmly; but the irregular troops, who had by their folly led the army into this plight, gave way before the English pikemen. The preachers, who were in vast numbers, set the example of flight. Many of the regiments of infantry fought most fiercely, but the battle was already lost. The Scotch cavalry were broken by the charge of the Ironsides, and in less than an hour from the commencement of the fighting the rout was complete. Three thousand Scotch were killed, and ten thousand taken prisoners.

Harry's regiment was but slightly engaged. It had been one of the last to march down the hill on the evening before, and Harry and Jacob foresaw the disaster which would happen. "If I were the king," Harry said, "I would order every one of these preachers out of camp, and would hang those who disobeyed. Then I would march the army on to the hill again. If they wait there the English must attack us with grievous disadvantage, or such as cannot get on board their ships must surrender. Charles would really be king then, and could disregard the wrath of the men of the conventicles. Cromwell will attack us to-morrow, and will defeat us; his trained troops are more than a match for these Scotchmen, who think more of their preachers than of their officers, and whose discipline is of the slackest."