As simple as this patent description from 1900:
And from then on... you can let your imagination take the lead:
ANYTHING IS POSSIBLE
The base from a Stella Model 104
The neck from Les Établissements Tarditi model "Nec Tar"
The security valve from Gaetano Delle Vedove Typo 6
The top from a "Rapida Express"
The Portafilter from a Szigony M.V. project Model "Elektro".
Something that would look like this:
My friend Lucio just posted on his Blog an interesting machine.
Any resemblance with the above is purely fortuitous.
For sure, more of these beauties will rise from oblivion...