Perhaps it kept the polar bears away!
Slight (?) thread creep: I work in the institution that has the original of Landseer's "Man proposes, God disposes" which shows a polar bear searching through the detritus of Shackleton's expedition. (No sign of a banjo!). Strangely, when the gallery was used as an exam hall, students were superstitious about the painting, claiming it brought bad luck to the candidate sitting near it so it had to be covered up (usually with a union flag!). I would have thought Millais' "Princes in the Tower" a more ominous subject!
RtS