A. B. McLean resigned as First Lieutenant.

The evidence

• “The original roster of Company D contained the following : George B. Ely, Captain, wounded at the battle of Antietam, September 2, 1862, discharged the service December 24 following; A. B. McLean, First Lieutenant, resigned October 7, 1862; Dana D. Dodge, Second Lieutenant, promoted to First Lieutenant March 18, 1862, resigned April 13 following; Albert F.”

  1879-history-of-rock-county/12-rock-county-ch06-politics-war-record.md, PDF p. 455 / book p. 459

  Butterfield, C. W., et al. The History of Rock County, Wisconsin: its early settlement, growth, development, resources, etc. Chicago: Western Historical Company, 1879. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871585.

  Grade A: Found on a page of one of our sources

  

• “The original roster of Company D contained the following: George B. Ely, captain, wounded at the battle of Antietam, September 2, 1862, discharged the service December 24 following; A. B. McLean, first lieutenant, resigned October 7, 1862; Dana D. Dodge, second lieutenant, promoted to first lieutenant March 18, 1862, resigned April 13 following; Ebenezer P.”

  1908-brown-rock-county/16-military-history.md, Vol. 1, PDF p. 360 / book p. 331

  Brown, William Fiske, editor. Rock County, Wisconsin: A New History of Its Cities, Villages, Towns, Citizens and Varied Interests, from the Earliest Times, Up to Date. Chicago: C. F. Cooper & Co., 1908. 2 vols. archive.org/details/rockcountywiscon01brow, archive.org/details/rockcountywiscon02brow.

  Grade A: Found on a page of one of our sources · may repeat 1879-history-of-rock-county, so not counted as independent