refitted as a polar exploration vessel. Her design as a bomb ship meant she had an unusually strong framework to resist the recoil of her heavy mortars; thus it was presumed she could withstand the pressure of polar sea ice, as well. Back expedition In 1836, command of Terror was given to Captain George Back for an Arctic expedition to Hudson Bay. The expedition aimed to enter Repulse Bay, where it would send out landing parties to ascertain whether the Boothia Peninsula was an island or a peninsula. Terror was trapped by ice near Southampton Island, and did not reach Repulse Bay. At one point, the ice forced her up the face of a cliff. She was trapped in the ice for ten months. In the spring of 1837, an encounter with an iceberg further damaged the ship. She nearly sank on her return journey across the Atlantic, and was in a sinking condition by the time Back sailed her into Lough Swilly, before beaching her at Rathmullan, Co. Donegal, Ireland on 21 September. <p> The admiralty dispatched the shipwright, William McPherson Rice, to refloat and repair Terror sufficiently to enable her sail to the naval shipyard at Chatham in Kent, where full repairs were carried out. Correspondence describing the repairs and the crew's sojourn in Rathmullan are held in the Royal Museums Greenwich collection. Back subsequently published a complete account of this voyage right up to the decommissioning of Terror in Chatham. Ross expedition In 1839 Terror was assigned to a voyage to the Antarctic along with Erebus under the overall command of James Clark Ross. Francis Crozier was commander of Terror on this expedition, as well as second-in-command to Ross. The expedition spanned three seasons from 1840 to 1843 during which Terror and Erebus made three forays into Antarctic waters, traversing the Ross Sea twice, and sailing through the Weddell Sea southeast of the Falkland Islands. The dormant volcano Mount Terror on Ross Island was named after the ship by the expedition commander. Franklin expedition Before leaving on the Franklin expedition, both Erebus and Terror underwent heavy modifications for the journey. They were both outfitted with steam engines, taken from former London and Greenwich Railway steam locomotives. Rated at , each could propel its ship at . The pair of ships became the first Royal Navy ships to have steam-powered engines and screw propellers. Twelve days' supply of