1760: a divider, compass-like item with a center (but no center is seen). It is a lot like some drawing-instrument compasses, but the handle is sideways, like it has to clear some obstacle. Maybe for visibility in mapmaking or mapreading use?
1761: holder for circular-saw blades, fits a pegboard. I want one!1762: souvenirs of aircraft flight certification?
1763: Guidance tool for working with pachyderms?1764: the glass item is a vacuum bell jar, the ground surface seals against a greased plate or gasket. The bracket is for holding the top seal in place when you raise the lid, as you must to open the vacuum chamber. It's a good dessicator, if you want to make dried flowers (or powdered herbs).