Holystone

Holystone is a soft and brittle sandstone that was formerly used for scouring and whitening the wooden decks of ships. It was used in the British and American Navy for scrubbing the decks of sailing ships. The term may have come from the fact that 'holystoning the deck' was originally done on one's knees, as in prayer. In realistic reference to their size, smaller holystones were called "prayer books" and larger ones "Bibles"; also, a widely quoted legend attributes the name "holystone" to the story that such pieces of stone were taken for use from St. Nicholas Church in Great Yarmouth. More plausible is the use of stones taken from the ruined church of St Helens, Isle of Wight; tall ships would often anchor in St Helens Roads (the strip of water immediately adjacent to St Helens) and take provisions and fresh water from St Helens before setting off on their journeys.