In article ,
Cheesehead wrote:

Big brass beast. No aperture or focal length markings.
Rear glass diameter is right at 3 inches.
Uses Waterhouse stops, but none included.
But finding info on 19th c. lenses is difficult.
It looks like a lot of history is missing or not readily available on
the WWW.

Do you own a copy of Kingslake?

--
Thor Lancelot Simon
"All of my opinions are consistent, but I cannot present them all
at once." -Jean-Jacques Rousseau, On The Social Contract