Mary Rose: refit, heavier guns, and stability

Mary Rose began as a roughly 500-ton-burthen carrack and was enlarged in the 1530s to perhaps 700-800 tons. The extent of the rebuild remains debated, although those estimates imply an increase of 40-60 percent. She was 34 years old when lost in 1545, so the familiar maiden-voyage story is wrong, and she appears to have sailed after the rebuild as well. Her armament nevertheless created a difficult weight-and-stability problem as guns became both more numerous and heavier. The available tonnage calculations offered limited help in judging that risk. England and Scotland also had an incentive to multiply the fighting effect of scarce personnel with stronger weapons, increasing the pressure for larger and more powerful ships.