172nd Siege Bty received reinforcements on 26 August when it was joined by a section from 415th Siege Bty, just arrived from Home. This allowed the battery to be brought up to a strength of six 6-inch howitzers. On 16 September 24th HAG was transferred to Second Army when that formation took over control of the faltering offensive: the Battles of the Menin Road, Polygon Wood and Broodseinde were highly successful because of the weight of artillery brought to bear on German positions. But as the offensive continued with the Battle of Poelcappelle and First and Second Battles of Passchendaele, the tables were turned: British batteries were clearly observable from the Passchendaele Ridge and suffered badly from CB fire, while their own guns sank into the mud and became difficult to aim and fire.