William Still, The Underground Rail Road (Philadelphia: Porter & Coates, 1872), 746.
Referred to by John Hunn, [Samuel Burris] was also a brave conductor on the Underground Rail Road leading down into Maryland (via Hunn's place). Mr. Burris was a native of Delaware, but being a free man and possessing more than usual intelligence, and withal an ardent love of liberty, he left "slavedom" and moved with his family to Philadelphia. Here his abhorrence of Slavery was greatly increased, especially after becoming acquainted with the Anti-slavery Office and the Abolition doctrine. Under whose auspices or by what influence he was first induced to visit the South with a view of aiding slaves to escape, the writer does not recollect; nevertheless, from personal knowledge, prior to 1851, he well knew that Burris was an accredited agent on the road above alluded to, and that he had been considered a safe, wise, and useful man in his day and calling. Probably the simple conviction that he would not otherwise be doing as he would be done by actuated him in going down South occasionally to assist some of his suffering friends to get the yokes off their necks, and with him escape to freedom. A number were thus aided by Burris.