21st Divisional Artillery Instruction 21 June 1916
A.A. & Q.M.G.
D.A.A. & Q.M.G.
On U day, the following telephone lines will be disconnected from the Divisional Exchanges:-
French Mission (RIBEMONT)
During operations “G” and Artillery calls will be treated as priority calls. Exchange operators will be instructed to cut off any other connection, if necessary, to put through a “priority” connection, on speaking the word “priority”