The Sea Floor post office in the Bahamas opened on August 16,1939 and closed some time in 1941. Large numbers of covers were postmarked at the undersea Post office and mailed to collectors all over the world. Some covers had pictorial cachets; others just had different varieties of cancels indicating the unusual place of posting. It must have been an interesting novelty for the collectors of the day.
You may find considerable interest in the Sea Floor covers. On eBay they sell for pretty good prices.
The undersea post office was created by US photographer John Ernest Williamson (1881-1966). He is remembered today as a pioneer in undersea photography and he was also deeply involved in the production of a number of motion pictures including one based on Jules Verne’s Twenty-Thousand Leagues under the Sea.
Williamson’s father had invented a kind of tube which could be used to facilitate communication and the flow of air down to depths of more than 200 feet. In 1912, Williamson designed a kind of chamber with a thick glass window which was attached to the tube and then lowered to the sea floor. From this vantage point Williamson was able to observe the undersea creatures and to take photographs. He called his invention the “Williamson Photosphere”.
The crystal clear water of the Bahamas allows the sunlight to penetrate deep down and it was an ideal location for Williamson’s Photosphere. In 1914, he shot his first under water motion picture in the Bahamas. This was the first of numerous expeditions many of which were scientific in nature.
His wife and daughter also helped him produce underwater films. They were shown during highly successful (and profitable) lecture tours throughout the United States. Much of the film material has now been donated to scientific institutions in the USA.
On July 1, 1938 the Bahamas issued a 4-penny stamp depicting the Sea Garden at Nassau. It is a delightful design featuring tropical fishes in a coral landscape. The design was based on a photograph by Williamson. This very same stamp was then used to frank many of the covers posted at the Sea Floor post office.
In 1939, the Bahamas-Williamson Undersea Expedition to film underwater was started. This was basically a scientific expedition but it also marked to creation of the Sea Floor post office. This undoubtedly was an excellent way of creating publicity for the expedition. The philatelic press of the day wrote about the Sea Floor post office and collectors all over the world ordered covers. It really must have increased the volume of mail from the Bahamas.
Williamson had quite a few famous visitors to his underwater chamber. It is known that the Duke of Windsor paid a visit to the photosphere. After abdicating from the British throne to marry the woman he loved, the ex-king served as governor of the Bahamas for a few years.
In 1965, the Bahamas issued a long set of definitives. The 1 shilling value once again depicted the sea garden. Williamson’s photosphere and the 1939 Sea Floor post office are depicted on the five-shilling denomination. The same pictures were used again in 1966 and in 1967 on new definitive stamps in connection with the change to decimal currency.
The cover shown above has a complete set of the 1937 Coronation issue along with the above-mentioned 4d Sea Garden stamp. All are neatly cancelled by the Sea Floor Bahamas dated postmark. The cachet depicts the Williamson Photosphere.The cover also has a straight-line cachet indicating that it was “Posted in the Williamson Photosphere”.
The cover was mailed by Grace Williamson at the US consulate in Nassau to Henry S. Villard at the Department of State in Washington, DC. Why and how this cover ended up on a dealer’s table in far away Sweden is anyone’s guess but stamps and covers do tend to get around.
The Sea Floor post office faded into oblivion in the early 1940′s. By then people all over the world had far more urgent matters to attend to.
However, there is an interesting twist to the story. In 2003, the Pacific nation of Vanuatu issued stamps depicting the underwater post office at Hideaway Island. Visiting divers and snorkellers can post special waterproof postcards at the underwater post office. It is certainly not the same kind of Sea Floor post office as the one in the Bahamas but I guess it helped create some interest in Vanuatu and its stamps.
Source & Courtesy : Christer Brunstrom from philatelydatabase.com