The microscope ("small-seeing instrument") is an optical device designed to magnify nearby objects.  Interestingly, the exact history of the invention of the microscope isn't clear:

  Spectacles (positive lenses) were first invented around 1285 in Florence, Italy.

  A single positive lens acts as a low-power magnifier (the simple microscope).

  Easy to imagine that two spectacles were held up and moved back and forth until a magnified view was obtained (the compound microscope).  In particular, this is essentially like using a telescope in reverse, and telescopes were being developed at around the same time as the microscope.

  Credit for the first (compound) microscope is given to Zacharias Jansen, around 1595 in Middleburg, Holland.

The First Compound Microscope