I thank you for your answers. They confirm to me that my Grandfather was fignting during Battle of the Scarpe with RWR.
So, a new question : do you know where was the 4th Divisional Signals Company between november behin of 1916 and mars 1917. My Grandfa met my french Grandma near Aubigny en artois which is 15 km form Arras and 15 km from Saint Pol.
Do you have a map of the area of Broodseinde (with 19 meter Hill) where my Grandfa was killed in Action.
There's a gap in the Div. diary from August 1916 to the beginning of Jan. 1917.
From 10th. Jan. 1917 the 4th. Div. were at Chipally S of Albert.
Knowing where your Grandfather was would depend on when he transferred from the RWR to the Signals.
19 metre hill is on this map.
You need to go to sector U square 18. It's NE of Langemark.
http://maps.nls.uk/view/101464861An overview of the 4/5th. Oct. 1917.
+ map from the 1/RWR diary.
2nd. map shows the location of 1/RWR next to 19 metre hill.