Mosocco's The Chronological Tracking of the American Civil War per the Official Records of the War of Rebellion,' records a
Skirmish at Ellison's Mill near Mechanicsville, VA May 23, 1862 and on June 26, 1862 The Battle of Mechanicsville, Beaver Dam Creek, or Ellison's Mill, VA.

Boatner's Civil War Dictionary lists Ellison's Mill, Va., 26 June '62, Mechanicsville, same date.

A Goggle search re Ellyson's Mill refers to the June 26 affair during the Seven Days Battles. Seems the correct spelling is Ellison.

George Martin