The only clue to the site of publication is contained in the initial essay that refers to publishing a magazine in the South-West, which, for July 1857, would mean St. Louis or the like. It is extremely well-written and contains essays, fiction, poetry and reviews as good as any major literary magazine of the time.
As an extra added attraction, there is a lengthy (just over six-page) essay by Elizabeth Barrett Browning entitled "Madame Luce and Her School". I have found no reference to this on any Browing website, nor does it appear on a Google search (though Madame Luce herself does).
Other literature includes "Hilda Fordyne, A Minister's Niece" by the well-regarded Bessie Rayner Parkes (who, rather curiously, also wrote an article on Madame Luce elsewhere). Another piece (unattributed) is entitled "The Myrtle Mystery. An Episode of My Life in Scotland."
So, I as I wrote above, I will happily pay $100 to anyone who can provide the name of the editor, location of publication and, obviously, the existence of another copy. (For those in the academic world, I will send the money to any institution or library as well).
While I won't pay extra, I am also intensely curious as to whether this work by the eminent Ms. Browning is now known to exist. My guess is that it is, but it would be really interesting if this is indeed a new discovery.
Good Hunting! Ain't old magazines great?