I recently read Harl Vincent's "Vulcan's Workshop," which was first published in Amazing Stories in 1932 and is now available as a free download at Project Gutenberg. And I'm happy to give a little plug to Project Gutenberg, since I probably wouldn't have come across the story elsewhere.
Though the story takes a turn toward the end that wraps things up too neatly, making too big a leap in terms of the changes we see in the main character for my tastes, I still thoroughly enjoyed the story. It is well-written, and the ideas underlying it are good old fashioned sic-fi-style fun.
You can download the story for free, put it on your e-reader, and read it all in an hour or so. It's an enjoyable story, certainly well worth the effort of popping by the website and doing the download.
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