If anybody thought that multiple observation is something relatively new, they were wrong. Already in year 1885, a multiwatcher microscope was manufactured, almost 130 years ago.
This microscope was manufactured by the company Geneva Optical Co. for the Swiss physicist Prof. Thury. It may have been designed to save time in demonstrations to groups of students. It had five objective lenseseyepieces tubes mounted in a central body that had a prism of 90°, which could be rotated to direct the light from the single target objective to any of the five eyepieces for an individual view.