Help identifying Broadhurst Clarkson & Co eyepiece

[trj]

Can anyone identify where this eyepiece may have originated from?

It came for free with some second hand telescope parts I bought.

I think it's brass (it's very heavy) and engraved with "Broadhurst Clarkson & Co".

It's not much use to me, it it useful? Is it worth anything?

Thanks.

More photos:

[Capricorn]

Seeing you are in or around Cambridge the only place that it might be useful is on the Northumbrian or Througood scopes at the IoA, but I doubt it as I think the eyepiece end of these have gone through updates to use eyepiece that are more modern. They are however of an age that could have been applicable when the scopes and that eyepiece were initially built.

[alan potts]

why not send an e-mail to telescope house, I believe the two companies got together or have some link in the day it was called Fullerscopes.

Alan

[ChrisLord]

I saw this eyepiece on eBayUK and successfully bid for it. It is a Pancratic erecting eyepiece, which is a basic four lens design dating back to the Dollond era. George Biddell Airy produced a pair of substantial papers dealing with the lens prescriptions necessary to correct both spherical & chromatic aberrations in the 1820's. Published in Cambridge Phil Trans.

I have measured the lens focal lengths and spacings, they are f=1".1; 2".2; 1".7; 0".7 s= 2".6; 2".8; 2".0

The first two lenses comprise the erector, the last pair a Huyghenian eyepiece. The Huyghenian section is held in a telescopic tube engraved at 1" intervals, the spacing being capable of increasing by 2".25. The wider the separation between the erector and the Huyghenian, the higher the erector amplification, which varies from x2 to x3.333

I have repolished the brass tube and relacquered it using golden yellow shellac lacquer dyed with turneric powder.

My browser won't allow me to upload phtographs, if you contact me: chrislord@brayebrook.demon.co.uk ;ll fwd them.

Chris Lord

[ikillyoo]

could anyone help giving any info on this telescope i picked up as a ornament for me and my 3 year olds man cave i used to really like astronomy but fell away from it but now he liked it right back in there.

I would just like some history so if asked i know a bit about it and i dont want my son just selling it at car-boot when i kick the bucket if its worth anything lol

As i said any help is very much appreciated

[John]

I've edited your post so that it can be read - black on dark grey and small text is too challenging !

I've posted a reply to your questions under the other thread you have started on this scope.