How to read map refs:
Q = area of sector map 57D.
18 = the 1 mile square section of Q.
a = the 1/2 mile square of 18.
Each small square is is divided into 10.
The start point is the bottom LH corner of the small square reading across to the right.
So the 1st. ref. is 5 which is the middle of a.
For the next ref. (4) the start point is the bottom LH corner of a & reading up.
Trenches in blue are British & trenches in red are German so you can see the Batt. are in recently captured German trenches taken during the Somme Offensive.
This map:
Martinsart Wood where they were earlier is in W3 & the huts in W.10.c & W.9.d.
http://maps.nls.uk/view/101465248Just a bit of logistical info. On the 20th. the 6/Borders were ordered up to the front line in R7a (see above link) which now ran through Beaumont Hamel & Beaucourt along the Beaucourt Rd. so your man at this time was about a mile behind the front line in what was now a British reserve trench.
The trench was described a having dug-outs & "quite comfortable".... apart from the shelling that is.