Flamsteed Astronomy Society

We started in Dome F, the Dome of Discovery exhibition which we had briefly explored prior to starting the tour proper. Some, as long in the tooth as I, will perhaps remember a previous Dome of Discovery on the South Bank in 1951 but this one was purely astronomically oriented.  Dome F contains the 38 inch ‘Congo Schmidt’ telescope which was built specifically for use in the Belgian Congo, only for the 60’s civil war there to prevent its installation.  It was later sold on, by the then presumed equivalent of ‘Del Trotter’s Astronomical Enterprises Ltd.’, to the Royal Observatory where subsequent tests indicated that it was unsuitable for observational research from this northerly latitude and had a warped mirror! (no chance of a refund I imagine?)

The party moved on to take in and discuss the merits of the 34 inch Hewitt camera (circa 1932) in dome C, the 13 inch Astrographic refractor in dome D (made in 1890), and the Thompson 30 inch reflector (1896) in Dome A. Interestingly, the lens of the 13 inch Astrographic refractor was taken to Brazil in 1919 to view the total eclipse and was instrumental (no pun intended) in vindicating Einstein’s predicted proposition that light from stars would be ‘bent’, or deflected, by the gravitational attraction of the Sun.


We also visited the Thompson 26 inch refracting telescope (1896) in dome E and the Yapp 36 inch reflecting telescope (1932) in dome B.  The Thompson is unique in this country in having a dome floor capable of being raised to facilitate access to the photographic plate-holder and also eyepiece of the guiding telescope. This was generally agreed to be a very expensive solution to a common observational problem with large instruments and Keith regaled us with a tale of when the floor had jammed, trapping many visiting dignitaries in the upper dome until expensively rescued.   Of particular interest is that the 12.8 inch Merz lens of the ‘guiding’ telescope attached to the 26 inch refractor was originally used in the ‘Great Equatorial’ telescope installed in 1859 by Sir George Airy at Greenwich and which was the forerunner of the present 28 inch ‘Great Equatorial’ with which we are familiar.


The 36” Yapp was the largest working telescope at Greenwich and is now the second largest at Herstmonceux. It was also, I believe, this instrument which boasted an impressively robust mount sporting a large brass plate proclaiming its manufacture by ‘Grubb Parsons – Newcastle-on-Tyne 1932’. “So what?” you may enquire but this is ‘The Flamsteed’ and we therefore enjoyed the benefit of inside information from Mike regarding its provenance. It seems that the Parsons of Grubb Parsons was a descendant of that famous forebear William Parsons, the 3rd Earl of Rosse (1800–1867) who was responsible for the design and construction in 1842 of ‘The Leviathan’, a 72 inch reflecting telescope at Birr Castle situated at Birr, or Parsonstown as it is also known, in central Ireland.  ‘Grubb’ was, incidentally, founded by Sir Thomas Grubb who was also Irish and whose son, Sir Howard, was responsible for the construction in 1894 of the Greenwich 28-inch Great Equatorial, and in 1896 of the Thompson 26 inch refractor situated in Dome E at a total cost of £5000!!


Keith entertains with legends of the old RGO  [Pic: Gil Newnham]

38-in ‘Congo’ Schmidt — warped mirror.  Useless. [Pic: Mike Dryland]

Flamsteed visit to Herstmonceux — June 14, 2008

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