Otheoscope with four vanes of clear mica
- Made:
- 1800-1899
Otheoscope with four vanes of clear mica, three other vanes of mica being attached to the side of the bulb (No. 25)
Otheoscope with four vanes of clear mica, three other vanes of mica being attached to the side of the bulb (No. 25)