Scottish National Dictionary (1700–)
BILL, n.3 The bar or beam of a harrow that bears the teeth. Eng. bull with same meaning dates from 1523 (see N.E.D.).
Rxb. 1798 R. Douglas Gen. View Agric. Rxb. 55 Note:
The late Sir David Kinloch shewed me a pair [of harrows], with the teeth in eight plates or rods of iron, each of which plates was very little shorter than the wooden bar, commonly here called a bull or bill, sunk into the bottom or lower part of it, and firmly bound to it by iron girds or hoops. [Obs. now replaced by bull according to Watson Rxb. W.-B. (1923).]
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"Bill n.3". Dictionary of the Scots Language. 2004. Scottish Language Dictionaries Ltd. Accessed 20 Jan 2019 <http://www.dsl.ac.uk/entry/snd/bill_n3>
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