Thomas Stevenson, 1880.
|Born||22 July 1818|
8 May 1887 (aged 68)|
|Employer||Northern Lighthouse Board|
|Spouse(s)||Maggie Balfour (m. 1848)|
|Children||Robert Louis Stevenson|
Robert Stevenson (father)|
Jean Smith (mother)
David Stevenson (brother)|
Alan Stevenson (brother)
Thomas Stevenson PRSE MInstCE FRSSA FSAScot (22 July 1818 – 8 May 1887) was a pioneering Scottish lighthouse designer and meteorologist, who designed over thirty lighthouses in and around Scotland, as well as the Stevenson screen used in meteorology. His designs, celebrated as ground breaking, ushered in a new era of lighthouse creation.
The youngest son of engineer Robert Stevenson, and brother of the lighthouse engineers Alan and David Stevenson, between 1854 and 1886 he designed many lighthouses, with his brother David, and then with David's son David Alan Stevenson. His wife's younger brother, James Melville Balfour, trained under D. & T. Stevenson and then emigrated to New Zealand, where he was first the marine engineer for Otago Province before he appointed Colonial Marine Engineer.
He married Margaret Isabella "Maggie" Balfour in 1848 and their son was the writer Robert Louis Stevenson, who caused him much disappointment by failing to follow the engineering interests of his family. 
Thomas Stevenson was a devout and regular attendee at St. Stephen's Church in St Stephen's Place, Silvermills, at the north end of St Vincent Street, Edinburgh.
In 1869, as a successful experiment into using the newly invented electric light for lighthouses, Stevenson had an underwater cable installed from the eastern part of Granton Harbour, and a light on the end of the Trinity Chain Pier was controlled from half a mile away by an operator on the harbour.
He examined wind and wave effects, and his analysis  is the first quantitative discussion of wave height as a (square root) function of fetch. His paper  is one of the first quantitative studies of wind speeds in the planetary boundary layer. Motivated by practical applications, these are fundamental contributions. He designed the Stevenson screen as a shelter to shield meteorological instruments, and this has been widely adopted.
Lighthouses designed by Thomas Stevenson
- Whalsay Skerries (1854)
- Out Skerries (1854)
- Muckle Flugga (1854)
- Davaar (1854)
- Ushenish (1857)
- South Rona (1857)
- Kyleakin (1857)
- Ornsay (1857)
- Sound of Mull (1857)
- Cantick Head (1858)
- Bressay (1858)
- Ruvaal (1859)
- Corran Point (1860)
- Fladda (1860)
- McArthur's Head (1861)
- St Abb's Head (1862)
- Butt of Lewis (1862)
- Holborn Head (1862)
- Monach Islands (1864)
- Skervuile (1865)
- Auskerry (1866)
- Lochindaal (1869)
- Scurdie Ness (1870)
- Stour Head (1870)
- Dubh Artach (1872)
- Turnberry Point (1873)
- Chicken Rock (1875)
- Lindisfarne (1877, 1880)
- Fidra (1885)
- Oxcar (1886)
- Ailsa Craig Lighthouse (1886)
- Richard Henry Brunton "Father of Japanese lighthouses"
- John Richardson Wigham Irish inventor and lighthouse engineer
- Waterston, Charles D; Macmillan Shearer, A (July 2006). Former Fellows of the Royal Society of Edinburgh 1783-2002: Biographical Index (PDF). II. Edinburgh: The Royal Society of Edinburgh. ISBN 978-0-902198-84-5. Archived from the original (PDF) on 4 October 2006. Retrieved 31 December 2010.
- "The Late Mr Balfour". The Star (503). 29 December 1869. p. 3. Retrieved 4 January 2015.
- Beaglehole, Helen (9 July 2013). "Lighthouses - A national system". Te Ara: The Encyclopedia of New Zealand. Retrieved 4 January 2015.
- Tyndall A Story of Lighthouses page 827
- Edinburgh Post Office Directory 1860
- The Nautical Magazine and Naval Chronicle for 1869. Cambridge Library Collection. 28 March 2013. pp. 614–615.
- Stevenson, Thomas (9 April 2009). Lighthouse Construction and Illumination. BiblioBazaar. pp. 165–166. ISBN 978-1103900954.
- Stevenson, T. The Design and Construction of Harbors: A Treatise on Maritime Engineering, seconded. Adam and Charles Black, Edinburgh
- Stevenson, T. (1880) Report on Simultaneous Observations of the Force of Wind at Different Heights above the Ground, Journal of the Scottish Meteorological Society, LI-LIV, pp.103–107