...mped at Mercersburg, sixteen miles distant, with a battery and a force of men, and General Averill was encamped at Greencastle, ten miles distant, with 2,500 cavalry. Why did they permit us to burn Chambersburg ? This is a question that has never been solved. They had three men to our one, as our force, all told, did not exceed 1,000 men. From a little pamphlet published a few months after the b...