Early to mid-20^th century Dallmeyer projection lens, inherited from my grandfather (a scientific instrument maker) in the 1960s and remained dry-stored since. 

Front section of lens (chipped at edge) was stored separately in a box, but I believe it belongs to this lens.

Serial number 271232

Lens engraved 5” GAUGE PROJECTION

Focal length 5” from mounting flange (measured) (with front lens fitted)

Threaded mounting flange, 44.2 mm diameter (measured over thread)

Overall length of lens (front to back): 80.5 mm

No visible scratches to lenses, but front lens is chipped at the edge

Weight 229 g

My knowledge of lenses and optics is limited, so please ask any questions.  Inspection welcome.

Collection welcome by arrangement from CB6 2NW