In 1756, while an officer in a military association, which was founded to resist the aggression of the French and Indians, he was wounded and forced to undergo terrible privations. While pursued by savage foes he sought refuge in the trunk of a tree, around which the Indians gathered and discussed the prospect of scalping him in the near future. When they left he escaped in the opposite direction and completely outwitted them. Then began a lonely march through an unbroken forest, where he was compelled to live on roots and herbs, and where the carcass of a rattlesnake proved his most nourishing meal. He finally succeeded in rejoining his command at Fort Cumberland. In recognition of his sacrifices and services in these Indian wars, the Corporation of Philadelphia presented him with a note of thanks and a splendid memorial medal. In the year 1758 he met George Washington and then it was that Pennsylvania lost a citizen. In Fredericksburg, at the time that Mercer came, lived John Paul Jones, and we do not doubt that they often met and talked of their beloved Scotland. During his first years in Fredericksburg, Mercer occupied a small two-story house on the southwest corner of Princess Anne and Amelia Streets. There he had his office and apothecary shop. The building is still standing. An Englishman, writing at this time of a visit to Fredericksburg, calls Mercer "a man of great eminence and possessed of almost every virtue and accomplishment," truly a sweeping appreciation. [Sidenote: _Mercer Joins Masonic Lodge_] He belonged to Lodge No. 4, of which George Washington was also a member, and he occasionally paid a visit to Mount Vernon. In September, 1774, the Continental Congress met in Philadelphia. The war cloud was lowering, it broke, and when the Revolution swept the country, Mercer was elected Colonel of the Third Virginia Regiment. An approbation of the choice of Mercer was prepared by the county committee, which set forth the importance of the appointment and was an acknowledgment of his public spirit and willingness to sacrifice his life. Colonel Mercer with his men and fifes and drums marched away from his home, bidding good-bye to his wife (Isabella Gordon), whom he never saw again. There is an interesting story of Mercer at Williamsburg. Among the troops which were sent there at that time, was a Company of riflemen from beyond the mountains, commanded by a Captain Gibson. A reckless and violent opposition to military restraint had gained for this corps the name of "Gibson's Lambs." After a short time in camp, a mutiny arose among them, causing much excitement in the army, and alarming the inhabitants of the city. Free from all restraint, they roamed through the camp, threatening with instant death any officer who would presume to exercise any authority over them. [Sidenote: _Mercer Quells a Mutiny_]