In these circumstances, while continuing to do all that was possible to improve my position on my right flank, I determined to press on with preparations for the exploitation of the favorable local situation on my left flank. At midday on October 21, 1916, during a short spell of fine, cold weather, the line of Regina Trench and Stuff Trench, from the west Courcelette-Pys road westward to Schwaben Redoubt, was attacked with complete success. Assisted by an excellent artillery preparation and barrage, our infantry carried the whole of their objectives very quickly and with remarkably little loss, and our new line was firmly established in spite of the enemy's shell fire. Over one thousand prisoners were taken in the course of the day's fighting, a figure only slightly exceeded by our casualties. [Sidenote: Part of Regina trench carried.] On October 23, 1916, and again on November 5, 1916, while awaiting better weather for further operations on the Ancre, our attacks on the enemy's positions to the east of Les Boeufs and Gueudecourt were renewed, in conjunction with French operations against the Sailly-Saillisel heights and St. Pierre Vaast Wood. Considerable further progress was achieved. Our footing at the crest of Le Transloy Spur was extended and secured, and the much-contested tangle of trenches at our junction with the French left at last passed definitely into our possession. Many smaller gains were made in this neighborhood by local assaults during these days, in spite of the difficult conditions of the ground. In particular, on November 10, 1916, after a day of improved weather, the portion of Regina Trench lying to the east of the Courcelette-Pys road was carried on a front of about one thousand yards. [Sidenote: Enemy losses.] Throughout these operations the enemy's counterattacks were very numerous and determined, succeeding indeed in the evening of October 23, 1916, in regaining a portion of the ground east of Le Sars taken from him by our attack on that day. On all other occasions his attacks were broken by our artillery or infantry and the losses incurred by him in these attempts, made frequently with considerable effectives, were undoubtedly very severe. [Sidenote: Preparations for attack on the Ancre.] On November 9, 1916, the long-continued bad weather took a turn for the better, and thereafter remained dry and cold, with frosty nights and misty mornings, for some days. Final preparations were therefore pushed on for the attack on the Ancre, though, as the ground was still very bad in places, it was necessary to limit the operations to what it would be reasonably possible to consolidate and hold under the existing conditions. [Sidenote: Permanent line of enemy fortifications.]