Grindstone

Man using a portable grindstone; painting by Goya

Large waterwheel powered grindstone. The user would lie on the plank above the grindstone while grinding metal items, giving rise to the phrase nose to the grindstone.

A grindstone is a round sharpening stone used for grinding or sharpening ferrous tools. They are usually made from sandstone.^[1][2]

Grindstone machines usually have pedals in which to speed and slow the stone to sharpen metal to the point of perfection.

A rotary grindstone − the earliest representation thereof,^[3] which is operated by a crank handle, is shown in the Carolingian manuscript Utrecht Psalter; the pen drawing from about 830 goes back to a late antique original.^[4] The Luttrell Psalter, dating to around 1340, describes a grindstone which was rotated by two cranks, one at each end of its axle.^[5] Around 1480, the early medieval rotary grindstone was improved with a treadle and crank mechanism.^[6]

References

1. Grindstones, archived from the original on 2010-02-10, retrieved 2010-02-10.
2. Knight, Edward Henry (1876), Knight's American mechanical dictionary, Houghton, Mifflin, pp. 1022–1023.
3. White, Jr. 1962, p. 110
4. Hägermann & Schneider 1997, pp. 425f.
5. White, Jr. 1962, p. 111
6. White, Jr. 1962, p. 167

Sources

• Hägermann, Dieter; Schneider, Helmuth (1997), Propyläen Technikgeschichte. Landbau und Handwerk, 750 v. Chr. bis 1000 n. Chr. (2nd ed.), Berlin, ISBN 3-549-05632-X
• White, Jr., Lynn (1962), Medieval Technology and Social Change, Oxford: At the Clarendon Press

See also

• Lathe
• Millstone
• Punch (tool)