Warren (now a brigadier general of the Massachusetts militia) was not unconcerned in that battle. Scouts of his had notified him on the 18th of April, that a detachment of troops was to march that night towards Concord: and then, remaining himself upon the watch, he saw Colonel Smith and 8 or 900 men embark for Charlestown. Knowing the stores and ammunition at Concord to be their object, he instantly sent messengers over the surrounding country, to give the alarm; and himself rode all night--passing so near the enemy, as to be more than once in great danger of capture. His messenger to Lexington was Col. Revere; who, on suddenly turning a corner as he passed through Charlestown, found himself close to a party of the British. In a moment he put his horse at full speed, dashed through them, and before they could well ascertain him to be a foe, was beyond the reach of the balls which they fired after him. It was his summons, that called forth the company of Lexington militia, upon whom, about sunrise on the 19th, was begun that bloody drama, of which the progress was to shake two continents, and the catastrophe to dissever an empire. Warren, sleepless and in motion throughout the night, hurried to the scene of action: and, when the enemy were retreating from Concord, he was among the foremost in hanging upon their rear, and assailing their flanks. By pressing them too closely, he once narrowly escaped death. A musket ball took off a lock of hair, which curled close to his head, in the fashion of that time. When his mother first saw him after the battle, and heard of this escape, she entreated him with tears not again to risk a life so precious. "Where danger is, dear mother," he answered, "there must your son be. _Now_ is no time for any of America's children to shrink from any hazard. I will see her free, or die." An exchange of prisoners was soon afterwards agreed on, to be carried into effect at Charlestown. Generals Warren and Putnam with two select companies of Massachusetts troops, repaired thither for the purpose. Here was a touching scene. The British and American officers, on meeting once more as friends after the recent strife had so rudely sundered their long subsisting ties of hospitality and mutual kindness, melted with tenderness, and rushed into each other's arms. The soldiers caught the infection: and mingled tears, and hands cordially shaken, softened for awhile the rugged front of war. Putnam and Warren entertained the British as guests, as sumptuously as the occasion allowed.