Illustration from 1911 Encyclopædia Britannica, article BUOYS.
Original text: The Courtenay whistling buoy (fig. 13) is actuated by the undulating movement of the waves. A hollow cylinder extends from the lower part of the buoy to still water below the movement of the waves, ensuring that the water inside keeps at mean level, whilst the buoy follows the movements of the waves. By a special apparatus the compressed air is forced through the whistle at the top of the buoy, and the air is replenished by two tubes at the upper part of the buoy. It is fitted with a rudder and secured in the usual manner.
Public domainPublic domainfalsefalse
This image comes from the 13th edition of the Encyclopædia Britannica or earlier. The copyrights for that book have expired in the United States because the book was first published in the US with the publication occurring before January 1, 1929. As such, this image is in the public domain in the United States.
Public domainPublic domainfalsefalse
This image comes from the Project Gutenberg archives. This is an image that has come from a book or document for which the American copyright has expired and this image is in the public domain in the United States and possibly other countries.
Note: Not all works on Project Gutenberg are in the public domain. Some public domain works may have trademark restrictions where all references to the Project Gutenberg must be removed unless the following text is prominently displayed according to The Full Project Gutenberg License in Legalese (normative):
This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.net.
Captions
Add a one-line explanation of what this file represents
Illustration from 1911 Encyclopædia Britannica, article BUOYS. Original text: The Courtenay whistling buoy (fig. 13) is actuated by the undulating movement of the waves. A hollow cylinder extends from the lower part of the buoy to still water below the