Lovely, Scarce Late 19th Century Nautical 14 Second Sandglass, Working

I've always got an eye out for antique sand timers, but don't come across them too often, and when I do they are usually priced well beyond my reach. This was a lucky find, and a cool one, a 14 second sand timer made for nautical use. Sailors used this type of sand glass to measure the speed of a vessel: a triangular piece of wood connected to a rope knotted every 43.7’ was thrown overboard into the sea; one sailor would let the rope out, another would watch the sand glass, and after 14 seconds, the number of knots would be multiplied by two to learn the speed of the ship. Carved of rosewood I believe, and all original, this one likely dates to the late 19th century. There is a cork stopper extending into the glass on one side, and a pontil on the other, typical of these, and the top on one side is stenciled in black paint to read "This End Up 14." 

4 13/16" t x 3" in diameter at top and bottom. Lovely antique condition and works beautifully.