[FOM] question about Boolean algebras

[Neil Tennant]

Does any fom-er know the answer to the following historical question?

I would like to know who might have been earlier than Stone ('The
theory of representations for Boolean algebras', Trans. AMS, 40, 1936, pp.
37-111) in proving that every finite Boolean algebra is isomorphic to the
Boolean algebra of all subsets of some set. Theorem 12 of that paper (on
p.52) is "A finite Boolean ring with at least two elements contains an
atomic basis S and is therefore isomorphic to the algebra of all
subclasses of a finite class Sigma in one-to-one correspondence with S."
(At this point in Stone's paper there is no historical reference that
would tell the reader whether the result had been established before. So I
should imagine this was the first proof of the result in question. But I
would like to verify priority.)

Neil Tennant