36" Reflecting Telescope at Cambridge Observa

I'm a founder member of the Society for the History of Astronomy and our 10th anniversary picnic was held at Cambridge observatory.
We have been here many times, but on this occasion we were able to see inside the observatory dome which held the Grubb Parsons 36" reflector. Its workings were explained to us by Dr Roger Griffin, who has had sole charge of it for the past 20+ years. He uses it to study stellar radial velocities.