By the end of September, on account of signalling equipment being obtained, it was possible to carry out training on much better lines than heretofore. This was fortunate, for it enabled intensive signalling training to be carried out prior to the battle of Cambrai. During this battle a much more complete system of signals was attempted, and wireless signalling proved invaluable in keeping in touch with rear headquarters and also in sending orders forward. On the first day of this battle a successful experiment in laying telegraph cable from a tank was carried out, five tons of cable being towed forward by means of sledges, the tank carrying 120 poles, exchanges, telephones, and sundry apparatus from our front line to the town of Marcoing. The signalling experiences gained during the battle of Cambrai proved of great value, the most important being that it became apparent that it was next to useless to attempt to collect information from the front of the battle line. Even if this information could be collected, and it was most difficult to do so, it was so local and ephemeral in importance as to confuse rather than to illuminate those who received it. Collecting points about 600 yards behind the fighting tanks were found to be generally the most suitable places for establishing wireless and visual signalling stations. At these stations officers were posted to receive messages and to compile them into general reports, which from time to time were transmitted by wireless to the headquarters concerned. After the battle of Cambrai the 4th Brigade Signal Company was formed. This Company was the first one to have a complete complement of trained Signal Service officers and men allotted to it. It carried out exceptionally good work during the operations in March 1918. At this time the complete organisation of signals in the Tank Corps may be shown graphically as follows: A. D. SIGNALS (Technical Instructions, Posting of Officers and Men, Control of all Signal Stores) ----------------------+------+------+------------+--------------+----- | | | | | 1st Tank Brigade 2nd 3rd 4th Wireless Repair Headquarters Signal Company (Tank Bde. Signals Coys). Section. Section. (administration, discipline, stores, erection and maintenance of lines, W.T. Stations). | ---+---+-----+-----------+--------------+-------------+----------+ | | | | | | Pool Occupation Section Section Section Transport. Dispatch Party. Battalion Battalion Battalion Riders. Headquarters. Headquarters. Headquarters. Early in 1918 the type of wireless apparatus as used in the signal tanks was changed to C.W. (continuous wave) sets, these being more compact, and greater range of action being possible with the small aerials the tanks had to use.