The Zim tool is a valve spring compressor for flathead engines. One jaw cradles the spring; the other presses against the block, the cam follower, or some other part of the valve train. Turning the knob causes the tool to open up, compressing the spring until you can get the spring retainer out, and then you can remove the valve (you have, before this, removed the head so you can reach the other end of the valve).
The bits on the Yankee screwdriver, if it's got the correct bits, will have a little indent in the shank. The chuck is either spring-loaded (push the collar up or down, can't remember right now but I think it's up) or threaded (twist the knurled collar to loosen it). Insert bit, turn it around until the notch in the end engages with the notch in the chuck, release or tighten the collar. Great tool for the kind of screws you find in household and furniture hardware: brackets for shades, curtains, blinds; furniture hinges; etc. This particular style was popular among telephone installers, and standard equipment back in the Ma Bell days; the drywall dust may be left over from some residential phone installer knocking holes in drywall to pull phone cables through the wall.
The long flat tool on the left is a seal puller for automotive and similar seals of the sort that keep oil and grease in place on axles, shafts coming out of motors, etc. Insert the hook under the seal to catch the steel frame inside the seal and pry gently. Very useful tool if you do automotive or mechanical work on equipment using that type of seal.
The Hargrave logo is intimately related to Cincinnati Tool.
