Across the Channel, in Great Britain, the operations of the Forestry Corps extended over six districts--four in England and two in Scotland. Forty-three detachments were spread over these areas, totaling 12,533 men at the end of the war, though of this number about 3,000 were attached labor or prisoners of war. In England the corps did especially noteworthy service in supplying the Royal Air Force, more specially for the defense wing. In a letter of appreciation written by Lord Derby, Secretary of State for War, it was indicated that on several occasions the men of the Forestry Corps had worked at the rate of ninety hours a week to supply timber needed in the construction of aerodromes for the aeroplanes used to repel hostile air raids. In November, 1918, at the conclusion of hostilities, the total strength of the Canadian Forestry Corps stood at 31,447, divided as follows: In France, regular officers, 425; attached officers, 53; other ranks, 11,702; attached, 1,039; prisoners of war, 5,021; giving a total of 18,240. In Great Britain there were: Regular officers, 343; attached officers, 49; other ranks, 9,624; attached labor, 1,926; prisoners of war, 1,265; making a total of 13,207. When hostilities ceased over 70 per cent of the timber in use on the western front by all the Allied armies had been supplied by the Forestry Corps. Up to December, 1918, the corps had supplied nearly 814,000,000 board feet of sawn lumber. "It is largely due," wrote Lord Derby, in the spring of 1918, "to the operations of the units of this corps in France that we have practically stopped the shipment of British-grown timber to France, thus saving cross-channel tonnage, while we are also able to save the shipment of foreign timber by having the production of the corps in England to meet the various national demands." CHAPTER VIII THE CANADIAN RAILWAY CORPS Never did railways as a means of transportation play so important a part in warfare as during the recent World War, in spite of the remarkable development of motor vehicles. It was her superior railway systems which gave Germany her principal advantage over the Russians on the eastern front, and as the great struggle developed, it became daily more obvious that the Allies would have to draw on their resources in railway construction to the uttermost to offset the initial advantage which Germany had in this respect on the western front. At first the French undertook to direct what railway construction it was thought would be necessary, but it was not long before the French Government was forced to call on the British for help. Finally the British found themselves unable to keep pace with the demand, and what was more natural than that Canada, the land of marvelous railway construction, should in her turn be appealed to?