If anyone ever wondered who pioneered adjustable throats and corrugations on iron planes, it was these guys in the 1860's. Nelson and Sidney Palmer, and Elliot Storke, respectively. Evidently it was decades before Stanley decided to copy the corrugations. I am amazed that there aren't more examples of bench planes with adjustable throats.
Sadly this plane makes a poor user because the blade support is nearly nil. The front knob is nearly bulletproof and the throat adjustment works wonderfully. Evidently they sunk all of their money into milling the toes of their planes because the frog is worse than bad- it is nonexistent. The blade is supported by about 3/8" of steel by the mouth and a flimsy cross rib at it's rear. I have never gotten chatter from a tapered iron before, but this plane made that experience possible.
Still it is interesting in a historical sort of way. Once I used it, however, the attraction factor switched from "That thing probably works great" to "rubbernecking at a car wreck."