The 4th Canadian Mounted Rifles were swept away by the storm of fire, but afterward it was learned that some parties had escaped. The garrison holding the last trench on the right reached the lines of the Second Brigade when night fell. The German advance was stubbornly resisted. Major Dennison fought a rear-guard action and got back to the second line with five men. The fortified post held by the 4th Canadian Mounted Rifles was blown up. One garrison was wiped out, and only three men got away from the other post. Between thirty and forty men were rallied behind the support line. The casualties were 637. The 1st Canadian Mounted Rifles Battalion on their left had also met with disaster. Their trenches were obliterated. The survivors retired to the apex, and some on battalion headquarters. The German attack launched just after 1 o'clock was made in four successive lines from the southwest. Mount Sorrel was reached and the German left flank began clearing the way, when the center attacked the 1st Canadian Mounted Rifles. Colonel Shaw in his redoubt found his right flank exposed, and was attacked on all sides. The garrison fought hard. Colonel Shaw fell and with him Major Palmer and Lieutenant Rowles. At last all the officers but two and most of the noncommissioned officers were killed and wounded. Lieutenants Key and Evans led fifteen survivors back to a fortified post before the apex where, with the help of stragglers, they held out until relieved the next day. The total casualties of the regiment were 367. The Princess Patricias had two companies in the firing line, one in a communication trench leading up to it, and a fourth in the support-line trenches. They were the next to withstand the German assault. The company on the right hand in the firing line was blown from the trenches. The survivors retired to the communication trenches held by the support company. The German wave engulfed all the left except the front-line company under Captain Niven, which turned and volleyed into the German rear. The company held ground for eighteen hours fighting hard and with excellent results. Their casualties were heavy, but the enemy too was hard hit.