/internal/media/dispatcher/7361/fullMMM 004761HourglassAmpulettaNavigation and Timekeeping / Time Measuring Devices20th century00An hourglass made of two pear-shaped bulbs of Glass united at their apexes held by a circular ring of Glass, having a narrow passage between them, allowing the sand to flow through. The bulbs were normally bound together using twine or wax but at the end of the eighteenth century one single Glass vessel was blown. The bulbs are held within a wooden framework.
Also known as sandglass, log Glass or watch Glass, they were normally constructed to run for a period of half an hour. For maritime purposes, half-minute, half-hour, hour and four hour sand Glasses were manufactured. At sea, an hour Glass was used by the seaman to mark his four-hour watches, where there were six watches in a day, each watch being split into eight bells. The ship's boy used to turn the hourglass and ring the bell. After eight bells, the watch was changed.20.7 x 12 cmMalta Maritime MuseumMalta Maritime Museum, Reserve Collection41242-3EEA.1965831720HourglassHeritage Malta881Glass bulbs blown into a single waisted Glass vessel, in a wood framework.Baddeley, J. (1993). 'Nautical Antiques & Collectibles', London: Sotheby's Publications.