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]
[edit] References
- ^ Grindstones, archived from the original on 2010-02-10, http://www.webcitation.org/5nRSwhf4Y, retrieved 2010-02-10.
- ^ Knight, Edward Henry (1876), Knight's American mechanical dictionary, Houghton, Mifflin, pp. 1022–1023, http://books.google.com/books?id=7jZVAAAAMAAJ&pg=PA1022.
- ^ White, Jr. 1962, p. 110
- ^ Hägermann & Schneider 1997, pp. 425f.
- ^ White, Jr. 1962, p. 111
- ^ White, Jr. 1962, p. 167
[edit] Sources
- Hägermann, Dieter; Schneider, Helmuth (1997), Propyläen Technikgeschichte. Landbau und Handwerk, 750 v. Chr. bis 1000 n. Chr. (2nd ed. ed.), Berlin, ISBN 3-549-05632-X
- White, Jr., Lynn (1962), Medieval Technology and Social Change, Oxford: At the Clarendon Press
[edit] External links
