May 21st:

1720: The earliest known “blind pool” appears, as the London Daily Post advertises a prospectus offering stock in a “Proposal for raising the sum of Six Millions sterling to carry on a design of more general advantage...and of more certain profit...than any undertaking yet set on foot.” There is no record of whether the investors who bought this pig in a poke ever earned any money, but we can safely assume that the “general advantage” and “certain profit” went to the promoters, not to the public.
Source: John Carswell, The South Sea Bubble (The Cresset Press, London, 1960), p. 156.

1927: Charles Lindbergh completes the first transatlantic flight as he lands his airplane, The Spirit of St. Louis, in Paris, 33 1/2 hours after taking off from Roosevelt Field on New York’s Long Island.
Source: Frederick Lewis Allen, Only Yesterday: An Informal History of the 1920s (John Wiley & Sons, New York, 1997, reprint of 1931 ed.), p. 164; http://lcweb2.loc.gov/ammem/today/jun11.html