On Thu, 25 Dec 2008 17:31:26 -0500, "Eisboch" wrote:


wrote in message
.. .


I often anchor overnight off Charles Island, which is one of the areas
where Bushnell did much of the testing during development of the
Turtle.


So, did he invent the screw propeller or did he invent a screw propeller
driven submarine?

Eisboch


I don't think there is conclusive proof that any one person invented
the screw propeller. My best guess is that Leonardo Divinci's drawings
inspired more than one person. There may be several who all figured it
out independently. They can all take credit without being dishonest.