Additional information can be found in a biographical sketch at the Archives of the Episcopal Church, and in Harrison’s A Soldier's Recollections, Leaves from the Diary of a Young Confederate, with an Oration on the Motives and Aims of the Soldiers of the South (New York: Longmans, Green and Co., 1910).
Robert H. Ellison
The User Guide for the Library of Appalachian Preaching is a Google Sheet that can be searched, sorted, and downloaded for offline use.
At the moment, McKim has only one sermon in the Library; it has a Guide of its own so the records will be complete. It includes the title, sermon text, date and place the sermon was preached, and so on. This information is available in the master list of sermons as well.
Lee the Christian Hero: A Sermon Delivered in the Lee Memorial Church, Lexington, Virginia, Sunday, January 20, 1907, on the Invitation of the Rector and Vestry
Randolph Harrison McKim
McKim preached this sermon to commemorate the centennial of Robert E. Lee, in a church that was named in his honor (in 2017, the name was changed from R.E. Lee Memorial Episcopal Church to Grace Episcopal Church. His topic is evident from the title; as he says on page 5, Lee “has a place of right in that noble army of the soldiers of Jesus Christ, who have done heroic service for God and for man in their lives.”