An unusually large brass and iron clockmaker's uprighting tool, stamped for Robert North and Sons, Bushey, probably late 19th/early 20th century The 10 inch circular cast brass stage fitted with three steel work clamping arms incorporating knurled locking screws and substantial vertical brass tube for a lower pump centring arbor, the top with shaped limb to carry the upper arbor, on three down-curved cast supports with angled pad feet drilled for fixing to a bench, the stage bearing stamp Rob’t North & Sons, 18 Rudolph Road, BUSHEY HERTS height of frame 53cm (21ins) high; with two other uprighting tools, both probably Swiss, circa 1900, 23cm (9ins) and 15cm (6ins) high respectively, (3). The firm Robert North and Sons of Bushey, Hertfordshire appear to have been instrument and possibly machinery suppliers most likely established during the first quarter of 20th century; and are still in business today. A rare one-minute torpedo timer attributed to Charles Frodsham but retailed by Robert North and Sons (dating to circa 1944) was sold in these rooms on September 20th 2017 (lot 313).Uprighting tools were mainly used to ensure perpendicular alignment of wheel pivots between clock or watch movement plates during the rebushing process. The basic standard design can be seen in a catalogue published by Berthoud in 1763 which is reproduced in Crom, Theodore R. Horological Shop Tools 1700-1900 on page 100 (figure 149). It is most probable that the principal item in the current lot is of Swiss manufacture and was either retailed by Robert North or used in their workshops.