For the history buffs, you may be interested to hear that there is an early explorers display at the National Museum at Canberra which includes Captain James Cook's original refractor telescope, used by him during his voyages around 1770.
You can get up very close to it, as it is in a glass display cabinet that you can stand directly over to have a very close inspection. It took my breath away. Just beautiful. Of course, it did not have the capacity for changing eyepieces...just the same fixed ocular which could be slid in and out a bit to focus. It looked to be about 2-2.5 inches in aperture.
I imagine image quality is poor compared to what we enjoy today, but with those dark skies in 1770, can you imagine what even naked eye observing would have been like?!
See Captain Cook's Telescope, circa 1770
