There are telescopes, and there are spyglasses. I own a 16 power U.S. Navy Mark 1 Spyglass mfg. in 1942 by Wolsak Corp. of Rocester, NY. that came from an auction in Washington state of stuff that supposedly came off of the USS Missouri.
This looks like a spyglass to me not a telescope but I guess if it can be mounted it's a telescope. Does it have crosshairs?