Year/Period |
1900-1930 |
Maker |
ONBEKEND/UNKNOWN |
Country |
Unknown |
Signature |
Unsigned |
Category |
Other optical equipment |
Subcategory |
Binoculars |
Size of the instrument (h x w x d) |
Length 17.5-43.5 × ø 4 cm |
Donated by |
R. Ketting, Vlaardingen, The Netherlands |
Inventory number |
SM 511 |
Brass telescope extendable to a length of 43.5 cm.
A telescope is, like binoculars, an optical instrument to view things well from a distance. Telescopes are monoculars, they have one eyepiece through which you have to look with one eye.
This telescope has been donated to the foundation by Mr. R. Ketting and comes from the legacy of his family from father’s side.

Polarimeter tubes
1900-1950

Porro prism binocular 7×50
BLEEKER
ca. 1953

Porro prism binocular 6×30
BLEEKER
ca. 1950

Achromatic magnifier 12× and 10×
BLEEKER
1940-1947