Battery Thompson (2)

From FortWiki
Jump to: navigation, search

Battery Thompson (2) (1902-1942) - Battery Thompson was a reinforced concrete, Endicott Period 8 inch coastal gun battery on Fort McKinley, Great Diamond Island, Cumberland County, Maine. The battery was named in G.O. 43, 4 Apr 1900, after Lieutenant Colonel Samuel Thompson, of the Massachusetts Militia, who effected the capture of Captain H. Mowett, then in command of certain British vessels in the harbor of Falmouth, and thereby averted for the time being the destruction of that town, now Portland, October, 1775. Battery construction started in 1898, was completed in 1902 and transferred to the Coast Artillery for use 11 Dec 1902 at a cost of $ 147,848.27. Deactivated in 1943.

L-R Battery Thompson (2 guns), Battery Acker (3 guns) and Battery Farry (2 guns)

Endicott Period (1890-1910)

Part of the Harbor Defense of Portland, Maine.

Originally built as an Endicott Period concrete coastal gun battery with three 8" M1888MII guns mounted on M1896 Disappearing carriages. This was a two story battery with the guns located on the upper level and the magazines below. Shells were moved from the magazine level to the gun loading platform by three Taylor-Raymond front loading shell hoists. No powder hoists were provided. Electrical power was furnished by the central power plant.

Battery Thompson (2) Armament (edit list)
Model Serial
Manufacturer Carriage Service
1 8" Rifle 278.5" M1888MII 25 Bethlehem Disappearing, M1896, #33, Lake Erie 1902-1942 See note 1
2 8" Rifle 278.5" M1888MII 5 Bethlehem Disappearing, M1896, #27, Walker 1902-1942 See note 1
3 8" Rifle 278.5" M1888MII 6 Bethlehem Disappearing, M1896, #29, Walker 1902-1942 See note 1
Source: RCW Form 1, 31 May 1919, CDSG, Berhow, Mark A. ed, American Seacoast Defenses: A Reference Guide, 2nd Edition, CDSG Press, McLean, VA, 2004, ISBN 0-9748167-0-1, pages 110-111
Note 1: Guns transferred to Watervliet 8 Jun 1943, carriages processed for salvage 15 Dec 1942. CDSG Gun Card Collection from NARA
Battery Thompson (2) Plan

World War I (1917-1918)

The U.S. entry into World War I resulted in a widespread removal of large caliber coastal defense gun tubes for service in Europe. Many of the gun and mortar tubes removed were sent to arsenals for modification and mounting on mobile carriages, both wheeled and railroad. Most of the removed gun tubes never made it to Europe and were either remounted or remained at the arsenals until needed elsewhere. The three 8" guns of Battery Thompson were listed for service abroad on 18 Jul 1918 but were ordered remounted before they could be shipped.

World War II (1941-1945)

Battery Thompson was obsolete at the beginning of World War II but still a part of the Harbor Defenses of Portland plan until the battery was declared surplus 15 Dec 1942. The guns were transferred to Watervliet on 8 Jun 1943 and carriages were processed for salvage 15 Dec 1942.

Current Status

Mostly private property on Great Diamond Island, Cumberland County, Maine. No period guns or mounts in place.

Location: Great Diamond Island, Cumberland County, Maine

Maps & Images

Lat: 43.687406 Long: -70.194239

  • Multi Maps from ACME
  • Maps from Bing
  • Maps from Google
  • Elevation: Gun #1= 70.204', Gun #2= 70.130', Gun #3= 75.600'


  • U.S. Army Corps of Engineers, FUDS Archives Search Report, Findings, Fort McKinley Military Reservation D01ME042402, December 1994, Portland , ME. Large pdf download
  • U.S.Army, Supplement to the Harbor Defense Project of Portland, Maine, (HDPB-AN-45), 11 Apr 1945, CDSG


Visited: No

Personal tools