According to the Bay City Times, "The experiment was conducted June 8, 1959, with 3,000 pieces of mail, all with 4-cent domestic stamps and 8-cent international stamps. All were postmarked from the submarine, the USS Barbero, at 9:30 a.m."
"The ship launched the missile, armed with canisters of mail, with the target being the Naval Auxiliary Air Station in Mayport, Fla. It took 22 minutes for the missile to reach its apex and then descend to the ground by parachute. "
"Once on the ground at Mayport, the canisters were opened and the mail sent to Jacksonville, Fla."
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