Reid & Auld, Edinburgh

A fine and rare longcase regulator. Circa 1818

One of only six known regulators by Thomas Reid and William Auld.

Case

Figured mahogany case with shallow arched hood over canted corners to a concave throat moulding. The dial surround lined in brass, long trunk door with figured mahogany panel, applied shaped moulding to the base on a plinth raised on block feet. Solid mahogany backboard measuring 3/4 of an inch in thickness,

Dial

The 11 inch shallow arched one piece silvered dial with regulator layout. The outer minute ring marked in tens, enclosing the subsidiary seconds dial above the Roman numeral hour ring. Signed in the shallow arch Reid & Auld Edinburgh. Fine blued steel hands.

Movement

The substantial eight day duration movement protected by the original wooden cover, with four large pillars, and shaped plates. Reid's deadbeat escapement with adjustable jewelled pallets and Harrison’s maintaining power. Long steel crutch with beat setting on the pallet arbor, six spoke crossings to all wheels mounted to high count pinions. The movement sits on substantial wooden seatboard mounted to the case with brass brackets set into the sides of the cheeks and secured via twelve screws. Steel pendulum rod with mercury filled glass jar and calibrated rating nut mounted on a large shaped cast iron bracket screwed to the backboard. Calibrated beat scale mounted to the backboard.

Height 6 ft 5inches (160 cm)

Thomas Reid

Thomas Reid was a most talented and inventive clockmaker, born in 1746 and apprenticed to his cousin James Cowan in Edinburgh 0n 9 October 1762 for six years. On completing his apprenticeship he went to work in London, returning to Edinburgh to carry on the business left to him by James Cowan in 1781. He made a clock for the tower of St. Andrew’s Parish Church and subsequently erected clocks all over Scotland. On 19th April 1790 he married Alexandria, the widow of William Auld, a printer burgess of Edinburgh. His stepson William Auld was apprenticed to him for 6 years in 1793 becoming a partner in the business in 1806. Located at at 8 Parliament Close and later 66 Princes Street in Edinburgh. This partnership was to become one of the most eminent in the history of Scottish horology

In 1811 he was commissioned by Lord Gray to design and make a regulator for a new observatory at Kinfauns Castle. The regulator was completed in 1811. A similar regulator was commissioned in 1813 by the Royal Observatory for Calton Hill, Edinburgh where it was attached to a stone pillar and was still in use in 1852 when it was used to drop a time ball on top of the Nelson monument and from 1861 it was used to fire the one o’clock gun at Edinburgh Castle.

For these, Reid devised an escapement similar to Mudges’ gravity escapement with the aim to detach the pendulum from the direct influence of the movement and give it a constant impulse. In his book Reid wrote that the Calton Hill regulator went for upwards of ten years without requiring any help, or even cleaning and the Kinfauns Castle clock was recorded as going for nine years without any attention. Unfortunately the Calton Hill regulator lost its original spring pallet escapement in the 19th century and the Lord Gray regulator lost its original spring pallet escapement in the early 20th century. Reid’s escapement was used in a modified form in LeRoys tank regulators over a century later achieving an accuracy of .01 second per day.

Thomas Reid also devised a zinc and steel compensated pendulum, this and his spring pallet escapement are illustrated and described in his book, ‘Treatise on Clock and Watchmaking” published in 1826. This book consisting of 466 pages with 20 plates went to six editions, including one in America, and is still a valuable reference today.

Thomas Reid died on the 24th September 1831 at the age of 85, his stepson William Auld left the Reid & Auld legacy Bequest to the Royal Society of Arts.