Greg Maxwell pwns. (If that link is blocked to you, read the text here.)
The question is: what other utterly and unambiguously public domain works is JSTOR charging outrageous sums for? And can we get copies to free?
(JSTOR are not a soft and fluffy nonprofit. They are an exceedingly murky nonprofit.)
Some are already uploaded to Commons. Here is the Wikisource project.
(I’m in the UK, where the state of the law concerning slavish copies of public domain works is still in a state of quantum uncertainty, and no-one quite wants to joggle it until the lay of the land is clearer. If I were in the US, where the law is unambiguous and tested, I’d be uploading as we speak.)