Bottle messages are not litter, as they are not discarded. Steps can be taken to reduce their environmental impact.
Bottles don’t have to be thrown into water. They can be left on transportation, mailed to random addresses, or left hidden in the woods, desert, or ice to be found far away in time if not in space.
As far back as 310BCE, Greeks were tossing bottles into the sea to test currents. They learned that the Mediterranean Sea was filled with water from the Atlantic.
In the 1500s, Queen Elizabeth I of England created an official position, “Uncorker of Ocean Bottles.” Anyone in England finding a bottle with a message was to bring it directly to the crown. The English had figured out ocean currents enough to use them as a conveyance for messages from spies.
The oldest bottle found to date had been afloat for 108 years. It was a science experiment.
Some bottle messages have traveled at least 10,000 miles.
One man, Harold Hackett, has thrown nearly 5,000 messages into the Atlantic. He has received over 3,100 responses. One took 13 years.
Bottle messages were dropped by the crew of Zeppelin L 19 before it crashed. The messages were recovered six months later.
Balloons have been used to send messages through the air. (There are environmental and safety concerns with releasing balloons.)
Bottle messages have been used to track where drifting World War II mines were likely to end up. They’re also used to track trash movements and also how currents affect fisheries.
Bottle messages have actually saved lives. The crew of a cargo ship was being held hostage and dropped messages in bottles to give information about their location and condition to NATO forces in the area. NATO stormed the ship and rescued them.