Optometer, objective or subjective
1831-1920
Optometer
Optometer, English(?), 1851-1930
1851-1930
Optometer, objective or subjective
1831-1900
Viewer, formed from truncated Stanhope type lens set in tube carrying mirror
1871-1900
Optometer, objective or subjective
1831-1900
Optometer, objective or subjective
1831-1900
Simple viewer
1871-1900
Optometer
Optometer
Optometer
Optometer, objective or subjective
1801-1900
Optometer, objective or subjective
1831-900
Optometer, objective or subjective
1851-1930