Built Masts Description, S.S. Great Britain, Bristol, England (UK), 2012

Even before being converted to sail, the S.S. Great Britain had the option of sailing if it ran out of coal. However, the ship was the largest ship in the world when built in 1845, being 322 feet long, 50'6" wide, and drawing 16 feet (although I don't know if this was the loaded draught). Displacement isn't reported consistently in the sources I've found, but is given as between 3,018 and 3,675 long tons. It was so large that a larger ship wasn't built until 1854, when the troop ship H.M.S. Himalaya set a new record of 4,690 tons displacement. So...this meant that the masts installed on the S.S. Great Britain had to be so large that the difficultly of finding large enough trees would have made traditional wooden masts impractical. For whatever reason, Brunel chose not to use iron masts, and the result was that instead "built" masts were used. These where constructed by combining wood from several trees, much like in cabinet making. This, in a sense, was another very modern feature of the S.S. Great Britain, as in the future there would be a need to preserve trees as the world's supply of old growth timber dwindled. Similar difficulties arose during the recent restoration of the U.S.S. Constitution.