Frank McClean was a gifted amateur astronomer who for the first  time discovered the spectra of oxygen in stars. As a result of his wealth he became a benefactor of astronomy and bequested a telescope to the Royal Observatory at the Cape of Good Hope.

Summary:

Frank McClean retired after only 11 years of working as an engineer. He spent the rest of his life as a very prominent amateur astronomer. He did important spectrographic work in astronomy, inventing his well-known star-spectroscope and also observed solar prominences. He published the spectra of 160 stars in the Journal Nature. McClean then made a bequest of a 61 cm (24 inch) telescope to the Royal Observatory at the Cape of Good Hope. In 1897 he visited the Cape Colony and using his telescope he photographed the spectra of another 116 stars. With this data  he discovered the presence of oxygen in spectrographs from Beta Scorpii, Beta Canis Majoris, Beta Centauri, and Beta Crucis. For this work he was awarded the “Gold Medal of the Royal Astronomical Society in 1899. [Wiki]

Frank McClean was the only son of a distinguished engineer, John Robinson McClean. He was born in Down, Ireland, on 13 November 1837. Frank was educated at  Westminster School, then studied at Glasgow University, where he studied under Professor William Thomson (1824-1907; later Lord Kelvin), and then to Trinity College Cambridge, graduating as 27th Wrangler in the Mathematics Tripos in 1859. Frank joined his fathers firm in 1859 but retired in 1870, 11 years later to focus on artistic interests and scientific pursuits [MNRAS, p338 / Wiki]

In 1871 the family bought an imposing property outside of Tunbridge Wells named Ferncliffe. McClean set up experiment with electricity and builds an Observatory where he stacked a 15-inch (38 cm) With-Browning reflector and a 6-inch (15 cm) Merz refractor on a sturdy equitorial mounting. During this time he started experimenting with spectroscopy and designed and patented a spectroscope that was named after him. This spectroscope was commercialized by the firm of John Browning of London. [Shears, p.2]

In 1884 the McClean family moved from Ferncliffe to a new home, Rusthall House, on the other side of Tunbridge Wells. McClean set up a new observatory with the addition of a solar observatory (polar heliostat) that was housed in the roof of the building. It seems that he liked the concept of stacking telescopes because he designed a telescope with at least two tubes (minus the finder scope) – twin refractors: a 10-inch (25 cm) for visual use and a 12-inch (30 cm) photographic, the latter with an objective prism. With this telescope he took the spectra of 160 stars in the Northern Hemisphere which were published in the journal Nature. [Shears, p.3]

The results of this work spurned him to bequest an even larger double telescope to the Royal Observatory at the Cape of Good Hope. This was known as the Victoria Telescope, but today popularly referred to as the McClean Telescope. He visited the Royal Observatory and by using his telescope he discovered the presence of oxygen in spectrographs from Beta Scorpii, Beta Canis Majoris, Beta Centauri, and Beta Crucis. For this work he was awarded the “Gold Medal of the Royal Astronomical Society in 1899. [Wiki / Shears,p.3]

Career:

Frank McClean joined his father’s firm of McClean & Stileman in 1859, becoming a partner in 1862.He retired in 1870.

Personal:

• McClean married Ellen Greg (1842-1909), of Escowbeck, Lancashire, in 1865. [Shears, p.2]
• They had three sons and two daughters.
• One son, Lieutenant-Colonel Sir Francis Kennedy McClean (1876-1955), also became a keen
  amateur astronomer under his father’s influence. He would also gain public acclaim as a
  pioneer aviator. He became a celebrity overnight n 1911 when he flew a Short Brothers
  aeroplane between the towers of Tower Bridge in London. [Shears, p.2] Francis is referred to as “The Godfather of British Naval Aviation” [Jarret]
• McClean was a great collector of art and antiquities.

Chronology:

• 1837 November 13: Born
• 1859: Qualify as Engineer / Start working at McClean & Stileman
• 1862: Become partner in McClean & Stileman.
• 1865: Marry
• 1870: Retire
• 1871: Ferncliffe at Tunbridge Wells.
• 1875: Built Observatory at Ferncliffe.
• Design and patent the McClean Spectroscope.
• 1884: Move to Rusthall House on the other side of the town Tunbridge Wells.
• 1887: Elected Fellow of the Royal Astronomical Society (FRAS)
• 1894: Bequest the Victoria Telescope.
• 1894: Honorary LL.D. Degree from Glasgow University.
• 1895: Elected Fellow of the Royal Society (FRS)
• 1897: Visit the Cape Colony and discover the spectra of oxygen.
• 1899: Awarder the Gold Medal from the Royal Astronomical Society.
• 1904 November 8: Died

• 15-inch (38 cm) With-Browning reflector
• 6-inch (15 cm) Merz refractor
• Design a spectroscope with a concave cylindrical lens. This was patented and named after McClean but  commercialised by the firm of John Browning of London. [Shears, p.2]
• Twin refractors: a 10-inch (25 cm) for visual use and a 12-inch (30 cm) photographic, the latter with an objective prism.
• Twin refractors: a 24-inch (61 cm) for visual use and a 18-inch (46 cm) photographic, the latter with an objective prism. This was bequested to the Royal Observatory at the Cape of Good Hope and was known as the Victoria Telescope.

• McClean Telescope at the S.A.A.O.
• McClean’s valuable collection of objets d’art from around the world, including glassware, ancient
  stone carvings and medieval manuscripts were left to the Fitzwilliam Museum, Cambridge, upon his
  death. [Shears]

Bibliography:

• Jarret, P.: “Frank McClean: The Godfather of British Naval Aviation”, Seaforth Publishing, 2011. ISBN-10: 1848321090
• MNRAS, v65, 1904/5, pp.338 -342.
• Shears, J.: Frank McClean and the Ferncliffe Observatory at Tunbridge Wells, Published in the Newsletter of the British Astronomical Association’s Historical Section  (date unknown)
• Wikipedia – Frank McClean: https://en.wikipedia.org/wiki/Frank_McClean

By Astronomer:

Archival: