The business of the Stevensons, civil engineers, of Edinburgh, originated with Thomas Smith, a whiteiron-smith, who became engineer to the Northern Lighthouse Commissioners when they set up their administration in 1786 under an Act 26 Geo III c. 161.

Robert Stevenson, Smith's son-in-law, gradually took over the work until in 1808 he severed his connection with Smith's business. After completion of the Bell Rock lighthouse in 1810 Robert Stevenson devoted himself to the profession of civil engineering, being engaged chiefly on sea-works, lighthouses, harbours and river-training works mainly in Scotland.

Robert Stevenson was joined in business by his sons Alan, David and Thomas (father of Robert Louis Stevenson). They were succeeded by David's sons, David A Stevenson and Charles A Stevenson. In 1913 D Alan Stevenson, son of Charles, became a partner.

The Stevenson family had a continuous connection as engineers with the Northern Lighthouse Board from 1786 until about 1936, when David A Stevenson resigned.

D Alan Stevenson, with Charles A Stevenson for a period, continued in business as a civil engineer until 1952 when he retired to study the history of sea-works, particularly lighthouses.

The firm practised under various titles: Robert Stevenson; Robert Stevenson and Sons; D and T Stevenson; D and C Stevenson; A and C Stevenson.

The plans prepared over many years by the Stevensons for the Northern Lighthouse Board, together with several hundred books of records, were given by the three partners to that Board in 1922. The plans prepared for the Clyde Lighthouses Trust concerning its sea-marks and the channel of the Clyde seawards from Port Glasgow were given to that body in 1952.

The firm advised the New Zealand Government on lighthouses from about 1865 to 1935.

The following individuals mentioned in the inventory were assistants of the firm: James Andrew; J H Park; James Ritson; C G Scott; John Steedman and R Shortreed. The latter was introduced to Robert Stevenson by a letter from Sir Walter Scott. Alan Brebner was taken into partnership about 1880 on a salary basis, otherwise partnership was restricted to the family.

The following civil engineers are mentioned in the inventory: Abernethy; Badeslade; Bald; Barron, Aberdeen; Dyce Cay, Aberdeen; Cunningham, Blyth and Westland, Edinburgh; Fraser, Inverness; Giles; Grainger and Miller, possibly Glasgow; Hawkshaw; Jardine, Edinburgh; Jopp, Aberdeen; Kinipple, Greenock; Kyle, Dennison and Frew, Glasgow; Leslie, Edinburgh; Locke; Meik, Newcastle; Mitchell; Mylne; Nimmo; Rendel; G and J Rennie; J Rennie; G Stevenson; Strain, Robertson and Thomson, Glasgow; Telford; Walker; Willett, possibly Inverness.

Denham and Mace were surveyors at Liverpool. Sir Samuel Brown designed the Chain Pier at Brighton and put forward many curious engineering projects. Gibb, Aberdeen, was a contractor and an ancestor of Sir Alexander Gibb.

The above notes are from the introduction to the inventory and were prepared by D Alan Stevenson.