The Battalion was finally mobilized at Aldershot Camp, N.S., on May 11, 1915. Lieut.-Colonel Gibsone proceeded direct to France to become A.A.G. of the 3rd Canadian Division, which was then in process of formation. At Aldershot Camp, N.S., the 40th was first inspected by the Duke of Connaught and Brig.-General H. M. McLean, who commented on their splendid showing. On June 21st, under the command of Lieut.-Col. A. G. Vincent, the 40th Battalion moved to Valcartier Camp, Quebec. Before leaving for Valcartier two drafts were despatched, one of twenty-five men to the 25th Battalion, and another of 250 men and five officers to England, as reinforcements. At Valcartier strenuous work by all ranks drew special mention of the 40th by Major-General Sir Sam Hughes at a General Review of the Camp a week before sailing. The Battalion was also inspected later at Valcartier by the Duke of Connaught and also by Sir Robert Borden. A week before sailing a third call was made for reinforcements, and again five officers and 250 N.C.O.’s and men, all picked, were despatched to England. Notwithstanding this great drain, on October 18, 1915, the 40th sailed from Quebec on the _S.S. Saxonia_, with a strength of 1,143 all ranks, under the command of Lieut.-Col. A. G. Vincent and the following officers: Major C. A. Andrews, Second in Command. Major J. C. Ditmars. Capt. J. S. Legge, Adjutant. Lieut. H. Fisher, Q.M. Lieut. G. M. Sylvester, Assistant Adjutant. Lieut. A. W. Cunningham, Sig. Officer. Lieut. H. St. C. Jones, M.G. Officer. Major Geo. Wood, Chaplain. Capt. E. Douglas, Medical Officer. Capt. G. H. Gillis, Paymaster. Major A. G. Nutter, O.C. “A” Company. Capt. W. E. Doane, Second in Command. Lieut. Geo. Campbell. Lieut. G. W. Anderson. Lieut. P. W. Freeman. Lieut. A. S. Allen. Lieut. J. Harley. Capt. C. R. Chisholm, O.C. “B” Company. Capt. H. P. Bell, Second in Command. Lieut. Mc.I. McLeod. Lieut. J. D. McIntyre. Lieut. W. W. Pickup. Lieut. H. H. Heal. Capt. A. M. Ross, O.C. “C” Company. Capt. G. W. Dwyer, Second in Command. Lieut. G. B. Murray. Lieut. A. S. Churchill. Lieut. C. E. Little. Lieut. L. W. Ormand. Lieut: D. H. MacKenzie. Capt. W. Letcher, O.C. “D” Company. Capt. E. R. Dennis, Second in Command. Lieut. B. F. Davidson. Lieut. F. P. H. Layton. Lieut. R. Jago. Lieut. L. W. W. Slacke. Lieut. F. G. Robertson. Lieut. A. Anderson.