Glas bowl in the shape of an Ancient Egyptian water clock.
© Science Museum / Science & Society Picture Library
This glas bowl in the shape of an ancient Egytian water clock was made by Whitefriars Glas Ltd, England. Alabaster bowls of this shape were used in Egypt for measuring time during the night. In use, these vesels were filled with water, which leaked out slowly from a small hole near the bottom; the time being indicated by the level of the water remaining within.