That is an amazing set that I have never seen before, either in person, photos, or catalogs or ads, here on GJ, or AA, or any other site. Nice find!
Are there any markings on the flip side of the ratchet handle? Please post a photo.
...an interesting concept; just hexagonal sleeves instead of sockets
An idea borne and morphed out of the late 1880s from industrial applications prior to the invention of the automobile. We've discussed a few sets with similar "adapters" or "reducers" etc on other threads using antique ratchet-drill like tools to turn nut and bolt heads. It's interesting that referred to as both "socket wrenches" and "bushings" on the label.
The ratchet, which is probably based on 666,202, filed by P. Lord in 1900, granted in 1901, can also be thought of as similarly transitional. The Bay State Tool Co made a series of single and double end ratcheting wrenches with various hex and square service openings. Exactly like the kinds of box end ratcheting wrenches we would later see from K-D, Snap-on, etc, still being made today. Like those, these early versions from Bay State had fixed "inserts" with fixed service opening sizes.
At some point between 1900 and 1908, they had the idea of using these ratcheting wrenches,
without fixed inserts with fixed service opening sizes, as universal ratchets, to drive detachable pressed steel socket wrenches of various service opening sizes of the kind that Mossberg would come to dominate in the market. I have a small set, linked
here. Which eventually led to the bigger and more famous Autokit sets (1908) that Sears eventually offered in their catalog in 1913, example linked
here.
I am making an informed hunch that your set came
before these.