 Complete the following phrase:  At the outbreak of war, Lieutet Colonel Tuxford attested for overseas service with the Canadian Expeditionary Force and was appointed to command the 5th Western Cavalry Battalion at Camp Valcartier. He took his unit overseas and led it during the Second Battle of Ypres in April 1915, as well at the Battle of Festubert. In March 1916 he was promoted brigadier general and appointed to the command of the 3rd Canadian Infantry Brigade, which he led during the battles of Mount Sorrel, the Somme, Courcelette, 