Message in a bottle
When it comes to messages in a bottle, we may think of adventures, shipwrecked people or romantic holiday greetings. Perhaps also of the slowness and coincidence with which these letters arrive – if they are found at all. Once upon a time bottles were posted in the name of science. The BSH keeps a worldwide unique collection of these scientific and historical bottle posts in its library archive.
Bottles as scientific current meters
What are the major ocean currents like? How can captains reach their destination faster and more safely? It was not easy to answer these questions in the middle of the 19th century. Where did the information about wind and currents on the world's oceans come from?
Of course captains passed on their knowledge to their successors. There were also astronomical determinations of current directions. Another type of research, however, goes back much further: even in ancient times people threw watertight and unsinkable vessels into the sea and waited to see where the current would take them. Georg Ritter Balthasar von Neumayer remembered this when he started the bottle post experiment on current dynamics in 1864.
Merchant ships helped science
The captains of German merchant ships were given an empty bottle and a small prepared form which – supplemented by the current date – was thrown overboard at a precisely defined position in the well sealed bottle. The finders of these bottle posts were asked to mark the notes with the location and date and to send them to the Deutsche Seewarte in Hamburg, a predecessor of today's Federal Maritime and Hydrographic Agency. According to expert opinion, there is a ten percent chance that a message in a bottle arrives somewhere intact and is found. Nevertheless, the scientists hoped that their evaluations would enable them to trace the path of the bottle and gain valuable information about ocean currents.
Accidental plastic animals provide valuable information
Even today, some merchant ships still deliver data to scientists. There are also curiosities like this: in January 1992 almost 30,000 green, yellow, red and blue plastic bathing animals went overboard a container ship in a storm in the tropical Pacific. Since then, many of them have been found on the Pacific and Atlantic coasts. Since his retirement, the American oceanographer Dr. Curtis Ebbesmeyer has dedicated his time to the pursuit of their dissemination routes.
Two thirds of the plastic toys have been driven south and found on the coasts of Australia, Indonesia and South America. The remaining third has travelled for more than 15 years to the coasts of England. The plastic animals first crossed the Bering Strait, which separates Alaska and Siberia. For several years they made their way through the icy Arctic to flow south along the east coast of Greenland and finally to reach Northwestern Europe with the North Atlantic Stream, a branch of the Gulf Stream. The plastic animals, which have faded in colour over time, thus provide valuable information about current conditions in the oceans.