Scottish National Dictionary (1700–)
SKY, n.2 Also ski. The part of the old Shetland and Orcadian single-stilted plough corresponding to the mould-board (Ork. 1814 J. Shirreff Agric. Ork. 51; I.Sc. 1866 Edm. Gl.; Sh. 1914 Angus Gl.). Also in combs. ear-sky, sky-ear, see Ear-sky, ivver-ski, millya-, nether-, see 1903 quot. and Iver. [skɑe]
Ork. 1728 H. Marwick Merchant Lairds (1836) I. 135:
16 dozen good pleugs four dozen skys. Ork. 1734 P. Ork. A.S. I. 65:
Four ploughs, whereof three wanting Skys and lives. Sh. 1795 Stat. Acc.1 VII. 585:
A square hole is cut through the lower end of the beam, and the mercal, a piece of oak about 22 inches long, introduced, which, at the other end, holds the sock and sky. Sh. 1808 Jam.:
Sky: a small board, about four inches in depth, used in the construction of the Shetland plough, in place of a mould-board. An old barrel-stave is generally used for this purpose. Ork. 1903 G. Marwick Old Roman Plough (1936) 9:
The pin next the sewch, or the lowest, is called the nether ski; this pin has to project two fingers' breadth below the wing of the markal pin. The next pin is the millya ski — a middle ski; the lower end of this pin must project three fingers' breadth below the markal pin. The next and last is the ivver-ski.
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"Sky n.2". Dictionary of the Scots Language. 2004. Scottish Language Dictionaries Ltd. Accessed 17 Jan 2019 <http://www.dsl.ac.uk/entry/snd/sky_n2>
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