A “stunning archive” from the family of Treasure Island author Robert Louis Stevenson is to be sold at auction.

The 19th century novelist, who also wrote The Strange Case Of Dr Jekyll And Mr Hyde, was from a family of engineers who pioneered lighthouse design and other civic infrastructure.

On Wednesday, an archive of the family’s personal papers, from the birth of Robert Stevenson in 1772 to the death of D Alan Stevenson in 1971, will be auctioned by Lyon & Turnbull live online in its rare books, manuscripts, maps and photographs sale.

Part of the sale is a letter sent by Robert Louis Stevenson from the yacht The Heron and a posed photograph of him in Samoa, which he sent to his uncle David Stevenson, who designed Edinburgh and Leith’s sewerage system and died in 1886.

The author’s grandfather, Robert Stevenson, invented intermittent flashing lights, and his descendants designed most of Scotland’s lighthouses.

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Also included in the Stevenson Collection, which spans 200 years and four generations, is an illustrated manuscript of designs for signals between the Bell Rock Lighthouse and the Arbroath Signal Tower, the oldest working lighthouse in the UK.

The structure off the coast of Angus was built between 1807 and 1810 into a treacherous sandstone reef, and it is considered Robert Stevenson’s most impressive construction.

The tome – Signals From The Bell Rock Lighthouse To The Arbroath Signal Tower – contains 28 hand-drawn and coloured illustrations detailing the workings of the building’s copper balls and flags, the main method of signalling between the two buildings.

Robert Stevenson also designed infrastructure such as railways and bridges, including Regent Bridge (1814) in Edinburgh.

Three of his sons, Alan, David and Thomas – who was the father of Robert Louis – followed in the family footsteps and designed lighthouses at home and abroad.

The Herald: Robert Louis StevensonRobert Louis Stevenson

D Alan Stevenson was the last of the Stevenson lighthouse engineers, and his collection of rare stamps and atlases is being sold as part of the collection.

The overall estimate for the sale of the Stevenson Collection: 1772-1971 is £45,000-£68,000.

Cathy Marsden, head of books and manuscripts at Lyon & Turnbull’s, said: “This is a stunning archive from a family who made a huge contribution to not only Scottish, but British engineering.

“Designing lighthouses, as you can imagine, was an extremely complex business, given the hazardous locations and the elements they had to withstand.

“This collection gives an insight into some of the finest engineering minds over multiple generations.

“We’ve already had a great deal of interest in the auction and expect competitive and enthusiastic bidding.”