Important to realise here that we're talking about the 42 Bn of the Machine Gun Corps, not the 42nd Company.
The MGC originally consisted of Companies, but these were later reorganised into MGC battalions.
Machine Gun Battalions were formed in the Divisions in the early months of 1918, by bringing together the four regimentally or brigade linked MGC Companies into a single command structure.
The Battalions took the number of their Division. Other MGC Battalions were formed outside the Divisions, or were detached to be placed under the command of higher formations.
42 Battalion Machine Gun Corps
Formed 23 February 1918 from the previous 4 separate companies. 1 Company was attached to each of the 3 infantry brigades and 1 company was in the Divisional Reserve.
125th MG Company was formed in Egypt, and joined 42nd Division, 4 March 1916. Moved into No 42 Bn, MGC 23 February 1918.
126th MG Company was formed in Egypt, and joined 42nd Division, 14 March 1916. Moved into No 42 Bn, MGC 23 February 1918.
127th MG Company was formed in Egypt, and joined 42nd Division, 14 March 1916. Moved into No 42 Bn, MGC 23 February 1918.
268th MG Company was formed in England in October 1917. Moved to France and joined 42nd Division, 20 January 1918. Moved into No 42 Bn, MGC 23 February 1918.
The date of birth of the child of Alexander McKENZIE showing him as Private Machine Gun Corps D Coy. 42 Battalion No.105918, was August Fifth 1918.
If the fours companies in 42 Bn MGC were lettered in number order that would make 268th Company Alexander's unit. The date figures as Alexander had not signed up by May 1916 when he was in a reserved occupation at Nobel Explosives at Ardeer.
As far as I can see the medal card doesn't give a date of signing up.
Like many other men in reserved occupations he later decided to volunteer.
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