When you connect to the IIS forum after a prolonged absence, a message comes up to the effect you've been a naughty person, and isn't it about time you posted something. A nice touch from the folks in the IIS engine room.
That message really did make me feel guilty, so I thought I'd post a few pics from a recent trip to the UK, or more specifically, to the Royal Observatory, Greenwich, (to give it its proper name, as opposed to the Royal Greenwich Observatory organisation, now defunct).
I don't have much else to offer as I was travelling light (not even binos) and the weather and light pollution around SE England only allowed a glimpse of a few stars of Ursa Major, one of my favourite childhood constellations. I did go up to The Outer Hebrides (you know, those remote islands off the west coast of Scotland) where two remarkably clear nights allowed some spectacular naked-eye views.
I hope you find the attached pictures and descriptions interesting and informative. If not, blame the ROG curators - most of it is lifted from their explanatory panels. That's one good thing about digital cameras, you can photograph signs and descriptions for later reading, something I never did in the days of film.
Just a couple of other observations. When I was last in London (16 years ago) the museums all charged for entry. Now most of them are free, including the Science and Natural History Museums, and the British Museum. Entry to the general areas of the ROG is also free, including the Transit Rooms, time-keeping museum, camera obscura, 28-inch refractor, and Flamsteed House and the Octagon Room. You do have to pay for entry to the on-site Planetarium which is a successor to the original one in Baker Street next to Madame Tussaud's.
The other thing is, that although the South Kensington and British museums allow unrestricted photography in their galleries, the ROG is different as I found out trying to get a (non-flash) picture of John Harrison's H4 chronometer. The attached images of interiors were taken before I was informed about about the rule ... honest.
Anyway, here we go.
01. Greenwich Park and the Royal Observatory, Greenwich
Just in case you didn't know, the official blurb says: The Royal Observatory, home of Greenwich Mean Time and the Prime Meridian line, is one of the most important historic scientific sites in the world. It was founded by Charles II in 1675 and is, by international decree, the official starting point for each new day, year and millennium ... (read the rest at nmm.ac.uk/server/show/nav.3191).
There's a detailed and fascinating history here if you have time to read the 13 chapters online:
http://atschool.eduweb.co.uk/bookman.../ROG/ROG01.HTM
The Royal Observatory Greenwich, Its history and work by E. Walter Maunder FRAS
02. Time Ball on the roof of Flamsteed House
Installed in 1833, the ball drops at 1pm daily. By the 1830s, most British sailors navigated using chronometers, which needed to be set accurately before sailing. This time ball allowed anyone in sight of the Royal Observatory to obtain Greenwich Time.
03. The Octagon Room.
This is one of the few surviving interiors by Sir Christopher Wren, the architect of St. Paul's Cathedral. Some serious astronomical work was done here, but it was built mainly 'for pompe', allowing important visitors to do some amateur observing in elegant surroundings.
The Octagon Room housed two very fine clocks which only needed winding once a year. These used very long (13-ft) pendulums concealed behind the panelling. They were sufficiently accurate to prove that the Earth turns at a constant rate throughout the year.
One of the orignal Thomas Tompion clock movements from 1676 is displayed in the Octagon Room. It employed for the first time a new type of mechanism, the 'dead-beat' escapement, which became the standard for precision pendulum clocks.
The portraits of the Observatory's Royal Patrons hang over the door. [I assume one is Charles II but after an hour searching the Internet I failed to find a proper description of either of them.]
The 32-inch astronomical quadrant [at left] is signed by John Bird [London, about 1760]. A contemporary engraving shows a similar,earlier quadrant standing on a wheeled tripod platform which allowed the astronomer to roll the instrument from window to window.
04. Replica telescope in the Octagon room.
The 'ladder' device allowed elevation of the instrument to observe different parts of the sky.
05. Astronomer's Study.
Flamsteed received only £100 a year as [the first] Astronomer Royal, a rather small salary even in the late 17th century. He resented the need to take private pupils to help pay for observing instruments: "... I am forced to Supply the want of my short and ill pay'd allowance by my extraordinary Labor".
06. The Greenwich Meridian ...
... is based on the crosswires in Airy's transit circle telescope [George Biddell Airy, 7th Astronomer Royal]. This is the 'prime' meridian used throughout the world and the one that traditionally divides the 'eastern' and 'western' hemispheres. However this is only one four meridians at Greenwich, the others being Flamsteed's, Halley's and Bradley's. British Ordnance Survey maps still use the Bradley meridian. [One could say there are in fact five: the GPS 'zero degrees' longitude lies 102.478 metres east of that metal strip in the Observatory grounds.]
07. Meridian fun for folks from all over the world.
08. Just me taking a photo.
(To be continued!)
