I think this might be a saccharimeter. I checked both eyepieces using a piece of polaroid and each of them contains a polarising element. The label on the base says “Griffin & George”. There is an extra label below this, that states “No.7709”.
with mr mackenzie
yes this is a saccharimeter. Had a student use this to look at optical activity as a CSYS project many years ago. Am pretty sure we borrowed one of these from the Physics department at Glasgow University so they might have some blurb on its use. Coincidentally, I was asked about the pupil’s project recently by my friend Dr. Norna Robertson who arranged the loan for me and I had a hunt around but couldn’t find it.