Update: 01-03-2025
Alan Stevenson was born on April 28, 1807 in Edinburgh. He was the eldest son of the famous lighthouse engineer Robert Stevenson, and brother of David Lillie and Thomas Stevenson.
Alan was educated at the High School and University of Edinburgh, where he took the degree of Master of Arts. As an advanced student of natural philosophy under the late Sir John Leslie he obtained the ‘Fellowes’s Prize.’
He prosecuted his studies at Twickenham under the superintendence of a clergyman of the Church of England. Afterwards entered his father’s office, to study for the profession of a Civil Engineer.
In the course of his education he had opportunities of seeing a great variety and extent of engineering works, comprising lighthouses, harbors, bridges, rivers, and canals.
In order to still further increase his practice, he, by the kindness of Mr. Telford, was sent on to the works of the Birmingham Canal. Thus Alan gained much practical experience, under William MacKenzie, the executive engineer of the canal.In partnervessel with his father, Robert Stevenson, and his brother, David Lillie Stevenson, Alan was actively engaged in general engineering until 1843. On the retirement of Robert Stevenson from the office of the Commissioners of Northern Lighthouses, Alan was appointed as his successor.
After that Alans' work practice was entirely confined to the lighthouse engineering. Especially by introducing the dioptric system. The first dioptric light introduced by the Trinity House of London in 1836, at the Start Point Lighthouse, in Devonshire. It was executed with Alans' design and under his supervision. Under his advice and management many important improvements were made in the lighthouse apparatus used in Scotland.
Alan designed and constructed many lighthouses in Scotland, but his biggest masterpiece was Skerryvore lighthouse on a rock near the island Tiree (Inner Hebrides).
To conduct this great work, during a period of five working seasons, his courage, patience and also his abilities as an Engineer were fully tested. It was found a general success accomplishing it and will ever be regarded as a triumph of lighthouse engineering, and as perhaps the finest combination of mass with elegance in architectural and or engineering structures.
After trying four different curves i.e, the parabolic, the logarithmic, the hyperbolic, and the conchoidal. Alan choose the hyperbolic curve for the Skerryvore tower, which has a diameter of 12.8 meters at the base decreasing gradually to 4.8 meter to the top. The height of the tower from the foundation to the top of the dome being 47 meter.
His principal contributions to engineering literature were his Account of the Skerryvore Lighthouse and the Treatise on Lighthouse Illumination, published in 1848, and republished by Mr. Weale, in his Rudimentary Treatises. He was also a contributor to the ‘Encyclopaedia Britannica,' the 'Edinburgh Philosophical Journal,' and to other scientific and literary periodicals.
Alluding to the Bell Rock and Skerryvore Lighthouses, a writer in the 'Quarterly Review' says: 'Taken altogether perhaps is this the most perfect specimen of modern architecture which exist. Tall and graceful as the minaret of an Eastern mosque, it possesses far more solidity and beauty of construction. It is as appropriate to the purposes for which it was designed as anything ever done by the Greeks, and consequently meets the requirements of good architecture quite as much as a column of the Parthenon.'
In proof of the correctness of this perception, it may suffice to say that the proportions of the Skerryvore tower (hyperbolic curve) was taken-over by Captain Fraser, R.E., for the Alguada Reef Lighthouse, constructed for the Indian Government, as stated in his report of the 31st of October, 1857.
The Emperor of Russia and the Kings of Prussia and of Holland presented Alan Stevenson with medals in acknowledgement of his merit as a Lighthouse Engineer, and the University of Glasgow conferred on him the degree of Bachelor of Laws.
On July 7, 1838 Alan Stevenson was elected and became Fellow of the Royal Society of Edinburgh, on proposal of: James David Forbes, 16/3/1838, (ms Proposal NLS Acc 10,000/45). (Billet 9/4/1838, 16/4/1838). He acted as a Member of Council from 1843 to 1845. After his illness (see later), when he tendered his resignation, the Council, in token of their respect, declined to accept his resignation, and continued to him the privileges of his Fellowvessel.
In 1844, Alan married Margaret Scott Jones. They together received four children, three daughters and one son (see the family tree at the right-hand). Alan has an early feeling for literary and classical studies, a feeling which he retained throughout his whole life, and used this often to relieve the monotony of his professional duties by pursuing his favourite studies. A volume of original poems, and translations from the Greek and Latin poet’s, printed shortly before his death, for private circulation among his friends, contained many pleasing odes from his pen, all of which breathe the truly earnest and Christian spirit which characterized his daily live.
Alan was affected by paralysis at the relatively early age of forty-five years. A year later, he gave up his post as Engineer of the Northern Lighthouse Board. In the following year (1854); and after a painful illness, he died on December 23, 1865 when he was forty-nine in Portobello (Edinburgh). He is buried in the Stevenson family plot in New Calton Cemetery (Edinburgh) with his wife.
The Commissioners of Northern Lighthouses, whom he had zealously served, recorded in their Minutes on the 3rd of January, 1866, 'their deep and abiding regrets for the loss of a man whose services had been to them invaluable ; whose works combining profound science with practical skill have not only conferred lasting honor and benefit on his country, but contributed largely towards the welfare of all, and whose genuine piety, kind heart, and high intellect made him beloved and respected by all his friends, and obtained for him the willing homage of all to whom his reputation was known,'