COMPOUND MONOCULAR MICROSCOPE

RETAILER: DOLLLOND

MAKER (ATTRIB):HUGH POWELL

c. 1840

SIGNED: 'DOLLOND, LONDON'

When purchased, two early Powell objectives 1/8 in. and 1/16 in. were present. Since then a pre-RMS Powell ½ in (with Lieberkuhn) , and 2 inch objective were added to the set. The 1/16 inch (dry) objective has an exceptionally short working distance, and a N.A. of approximately 0.64 characteristic of the earliest version of this objective as first developed by Hugh Powell in 1840.