32. Telescopic tubes
end XVII cen.?
author and place unknown
pasteboard
length 240 cm + 120 cm, diameter 12 cm
[Inv. MdS-128 and MdS-129]

The two tubes in question are made of pasteboard, probably built at the end of the XVIIth century. There is no mention of them in the inventories.
It is possible they were used as mounts for certain lenses. At the ends there are signs of a paper joint designed to join them and make them into a single tube. The longer tube is in fact made up of two shorter tubes joined together by the system just described.
The total length of approx. 345 cm matches the focal length of the unsigned object lens (diameter 67 mm, 5 mm thick at edge, and focus 350 cm), in green-tinted glass, with very few bubbles, one of which is large; it is not sure if this object lens belongs to the surviving exemplar of the two 8-foot Germanic telescopes [file 26].
Other tubes that have disappeared could however exist, leaving open the hypothesis that it is a part of the long "tubus chartaceus" of Montanari’s 11.6-foot (450 cm) telescope [file 24].