Late in March 1860 numerous people throughout London received the following invitation:

By twelve o’clock on April 1st a large crowd had gathered outside the tower. However, no lions had been kept in the tower for decades, so the people went home disappointed. This prank had a very long pedigree. An instance of it was recorded as far back as 1698. For decades, it had been regularly perpetrated (on a smaller scale) upon unsuspecting out-of-towners. (See article: Washing the Lions)