An Unopened 1929 Envelope Posted to New York via Airship “Graf Zeppelin”

An unopened envelope, measuring 171x90mm, near mint condition. The sender is factory director Emil Müller from Bohemia, the recipient is Rudolph Dinnebier in New York City. The letter was sent via the airship “Graf Zeppelin” on its first America journey in 1929, however, a stamp states that transportation was delayed due to the abort of the journey. The letter was sent on May 16, 1929 and arrived in New York on August 5.