The lens is a
50mm Bausch & Lomb Tessar F.3.5 to F32. Patented February 24, 1903. The
glass is quite clean and has no lens fungus. There is some slight oil film
on the rear side of the front element but this is from the lens
lubrication and could be cleaned and removed easily. Actually, I would
shoot with this lens just like it is. I'm sure the low contrast image
quality produced from this early uncoated lens would only be complimented
while the image would not be degraded enough to warrant lens disassembly.