The Tower of London ghosts

Ghost reports from the Tower of London, centred on the Jewel House, where the Keeper of the Crown Jewels described an apparition in 1817 and a sentry is said to have died after seeing a bear-like figure.

The main account comes from Edmund Lenthal Swifte, Keeper of the Crown Jewels, in a letter printed in Notes and Queries in 1860. Wikipedia dates his sighting to October 1817 in the Jewel House. Swifte wrote that he was handing his wife wine mixed with water when she cried out. Looking up, he saw a tube-shaped form, about as thick as his arm, floating above the table, below the ceiling. It seemed filled with a thick, pale blue fluid that kept churning, and it stayed for around two minutes. Charles Harper, retelling the story in 1907, says people doubted Swifte when he told the story the following day, and the chaplain asked him whether two people's senses could be fooled as easily as one.

The same issue of Notes and Queries carried a note by George Offor about a sentry at the Jewel House in January 1816. Offor wrote that noises had been heard there, and that at midnight the sentry saw a bear-shaped figure cross the paving and vanish down the steps. The soldier collapsed, recovered enough to describe it, and died within a few hours. Offor called him brave and of good character, and said the scare was put down at the time to phantasmagoria, trickery with projected images. The governor and the regiment's colonel doubled the guard, and the ghost stopped. Wikipedia gives a different timing: the sentry died of fear some days afterwards.

Alden Gregory, a curator at Historic Royal Palaces, points to older stories of the same kind. He notes that the Hereford Journal reported in 1789 that noises and spectres had troubled the Martin Tower for a long time, and that around 1782 a guard there was said to have been thrown from his post by a spirit resembling a furious beast. Wikipedia lists other ghosts reported at the Tower: Lady Jane Grey, Henry VI, the Princes in the Tower and Margaret Pole.