Hare ophthalmoscope 1915
Hare ophthalmoscope from around 1910 was of two types. One was the old style using reflected light from a mirror and the other was a battery lit model. This one is the same as the battery lit one except it has a power cord which would have been hooked to a transformer to provide the light.
This unusually shaped instrument has a lens disc with geared overlapping dials to give a continuous change of lens power from minus 1 to 29D and plus 1 to 20D in 1D steps. There is also an addition of a plus 20D lens on the reverse side which can be moved up into position by a lever on either side of the column.
The mirror is slotted from the base and focus of the illumination can be changed by sliding a knurled ring on the column either up or down.
The back side of the scope has the logo of Genothalmic (General Optical Co. Inc.)