The accrual consists of holograph correspondence written primarily to his mother from the trenches and war front in Europe, together with a typescript transcription of the letters; a photograph of Macgowan with (apparently) two members of his battalion; programme for a Brussels Ball; clippings; and 11 maps used by Macgowan to direct his troops in battle. Most of the letters have been chronologically arranged by Macgowan; some letters are missing from the sequence, including a large gap 42-53.
The fonds consists of holograph correspondence written primarily to his mother from the trenches and war front in Europe, together with a typescript transcription of the letters; a photograph of Macgowan with (apparently) two members of his battalion; programme for a Brussels Ball; clippings; and 11 maps used by Macgowan to direct his troops in battle. Also included are aerial photographs of three regions of north-west France together with a map of north-west France (Denain region). Some of the photographs have holograph additions to them, largely for the purpose of identification of towns or other significant features.