Barograph clock by A Cumming, 1766.

Barograph clock by A Cumming, 1766.

Bain electric clock mechanisms, c 1841.

Bulle electric clock, c 1920.

Bain electric clock, c 1850.

Microtome, 1770.

Barograph, 1941.

Alexander Bain, Scottish telegraphic inventor, 1874.

Alexander Bain, Scottish telegraphic inventor, c 1870s.

Pendulum clock.

'Arbroath Railway Terminus at Dundee', Scotland, mid 19th century.

Royal Air Force aircraft controller at work