Many witnesses testified that the ship had a very long roll (a reluctance to right herself after leaning into a swell). One passenger on her maiden voyage said that when in the Southern Ocean she developed a list to starboard to such an extent that water would not run out of the baths, and she held this list for several hours before rolling upright. This passenger, physicist Professor William Bragg, concluded that the ship's metacentre was just below her centre of gravity. When slowly rolled over towards one side, she reached a point of equilibrium and would stay leaning over until a shift in the sea or wind pushed her upright.[15]
Other passengers and crew members commented on her lack of stability, and those responsible for handling the ship in port said she was so unstable when unladen that she could not be moved without ballast.[16] But for every witness of this opinion, another could be found who said the opposite. Both former passengers and crew members (ranking from stokers to a deck officer) said the Waratah was perfectly stable, with a comfortable, easy roll.[17] Many said they felt she was especially stable. The ship's builders produced calculations to prove that even with a load of coal on her deck (that several witnesses claim she was carrying when she left Durban) she was not top heavy.[13]