William Tregarthen Douglass (1857-1913), M.I.C.E, Engineer.
Nephew of William Douglass
1874/6 Student attached to the Institution of Civil Engineers; address: Trinity House, London E
1879 Joined the I Mech E
Had son Percy Cuthbert Douglass Douglass
1913 Obituary 
WILLIAM TREGARTHEN DOUGLASS was born at Solve, Pembrokeshire, on 23rd March 1857, being the son of the late Sir Douglass, who was for many years Engineer-in-Chief to the Trinity House.
He was educated at Dulwich College and King's College, London, in the Applied Science Department.
Having served his pupilage at the Trinity House for three years, from 1875 to 1878, under his father, and at the engineering workshops at Blackwall, he studied optics and the manufacture of optical apparatus at Messrs. Chance Brothers' lighthouse works, Birmingham, under the late Dr. John Hopkinson, F.R.S.
From 1882 to 1887 he was resident engineer in sole charge of the difficult work of strengthening and improving the Bishop Rock Lighthouse, Scilly Isles, and he erected a lighthouse on Round Island, in the same locality.
He also carried out a large amount of engineering work of the same nature, and at the time of his death was consulting engineer to the Governments of Western Australia, New South Wales, and Victoria, and inspecting engineer to the Royal National Life Boat Institution, for which he designed their life-boat stations and slipways, etc.
At Cromer he constructed the sea wall, and at Lowestoft his system of groynes was adopted by the local authority.
In 1899 he was selected by the Secretary of State for India to inspect and report on the whole of the lighthouses of India and Burma, comprising ninety stations and covering an immense stretch of coast and river line. He was the author of several books on lighthouses, and on the lighting of estuaries and rivers.
His death took place by drowning on 10th August 1913, at the age of fifty-six. While out with his son in a sailing-boat, the latter capsized when off Start Point, near Dartmouth, and sank. The son, who was picked up by a pleasure steamer, swam with his father for about three-quarters of a mile, when the latter became exhausted and was drowned, in spite of efforts made by his son to keep him afloat.
He was elected a Member of this Institution in 1887; he was also a Member of the Institution of Civil Engineers, and a Fellow of King's College, London.
1914 Obituary 
WILLIAM TREGARTHEN DOUGLASS, son of the late Sir James Nicholas Douglass, Engineer of the new Eddystone Lighthouse and other notable works, was drowned off Start Point by the capsizing of a small sailing-boat on the 10th August, 1913.
Born on the 23rd March, 1857, the subject of this notice served a pupilage under his father, then Engineer to the Trinity House, between I875 and 1878, and was subsequently engaged as Assistant Engineer on the erection of the Eddystone Lighthouse, and as Resident Engineer on the difficult work of strengthening and improving the Bishop Rock Lighthouse. Later he erected a lighthouse on Round Island, and carried out many similar works round the coasts. At the date .of his untimely death he was Inspecting Engineer to the Royal National Life-boat Institution, and Consulting Engineer to the Public Works Loan Board and to various lighthouse and harbour authorities.
He was the author of Papers presented to The Institution on "The New Eddystone Lighthouse," "Bishop Rock Lighthouse," in conjunction with Mr. J. A. Purves, "Improvements in Dioptric Apparatus for Lighthouses," and "Foreshore Protection and Travel of Benches," for two of which he received a Telford medal and a Telford premium.
In 1912, at the invitation of the Council, he delivered before the Students of The Institution the Vernon-Harcourt Lectures on "Works for the Prevention of Coast-Erosion."
He was only 56 when the accident occurred by which the profession at large was prematurely deprived of an able engineer and his many friends sustained an irreparable loss.
Mr. Douglass was elected an Associate Member of The Institution on the 23rd May, 1882, and was transferred to the class of Members on the 6th December, 1887.
1913 Obituary 
WILLIAM TREGARTHEN DOUGLASS was born on 23rd March, 1857.
He received his early education at Dulwich College, and subsequently studied in the Applied Science Department at King's College, London.
He served for three years, 1875-8, as an articled pupil to his father, the late Sir James N. Douglass, F.R.S. From 1878 to 1882 he was resident engineer during the pulling down of the old Eddystone Lighthouse and the erection of the present lighthouse. He devoted the whole of his attention to lighthouses, marine illumination, harbour construction, and sea-defence works, and was responsible for the construction of thirty-eight lighthouses.
At the time of his death he was consulting engineer to the Governments of Western Australia, New South Wales, and Victoria, also to the Royal National Lifeboat Institution and various other bodies.
He was drowned on 10th August, 1913, owing to a boat, in which he had gone out sailing with his son, being capsized off Start Point, near Dartmouth.
He was elected a Member of the Institution in 1891.