Available for PDF download is a copy of the pamphlet by Conway P. Wing, A Ministry of Fifty Years. A Discourse Delivered February 20, 1881, Before the First and Second Presbyterian Congregations of Carlisle. He heads the first page of the discourse as a “Sermon” with Romans 5:4 and 1 Thessalonians 5:21 as his texts, but the verses have little to do with his presentation. The discourse covers his whole ministry and not just the Carlisle years. It includes comments about some of the general changes he had seen in America during his life.
Reading the biography of Dr. Wing that has been posted on Presbyterians of the Past before reading the pamphlet may be helpful.