At 12:41 29/03/05 +0100, Chris Kelland
>My understanding of the 'oval' shaped wheel-pit is that
>the wheels were not all the same size, as the axle area being wider than the
>outer part of the wheel due to the axle holding other working machinery.
There was also a structural reason for a wheel having a greater width at
its axle in relation to its breast, ie the width at the circumference. For
example, the wheel for sale at Wheal Vervale, Trentishoe parish in North
Devon, in 1846 was 36 feet in diameter with a 23 inch breast - a narrow
breast but large in diameter to take advantage of a limited volume of water
on the site (West Briton, 6 Nov. 1846). It was also constructed of oak - a
heavy wheel and probably of much earlier construction than the mid century
date would suggest. To mount such a wheel on a an axle of less than 2 feet
would result in it being unstable and an axle of, perhaps, twice that
length might be expected with the spokes tapering in towards the
circumference. Such a wheel would be mounted in an oval or asymetric wheel
Dr Peter Claughton,
Blaenpant Morfil, nr. Rosebush, Clynderwen, Pembrokeshire, Wales SA66 7RE.
Tel. +44 (0)1437 532578; Fax. +44 (0)1437 532921; Mobile +44 (0)7831 427599
Hon. University Fellow
School of Historical, Political and Sociological Studies (Centre for South
Western Historical Studies)
University of Exeter
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