river boat questions

My first question is: What is a "chest" on a boat.. if somone says you need a boat that is "deep-chested" what does that mean? Also, I have heard of large rudders that are put on boats on rivers that sweep back and forth, and push you forward like a fish tale does. Is anyone familar with this. Could you tell me what its called.. and is there any pictures of this anywhere.. or plans for somthing like this. thanks for any information you can give me.

-Eric

 

The term deep chested usually means that the forward underwater part of the boat is deep and perhaps wide. Boats designed for hauling heavy loads frequently have that characteristic. The term is more often applied to sail boats but could be descriptive for a power boat. The Nina, Pinta, and Santa Maria, for example, were deep chested.

The process of wiggling the rudder back and force for the purpose of propelling the boat is called "sculling". Racing sailors call it "cheating" because it is strictly against the rules. Sculling is sometimes used to move the boat short distances but only when the weather is mild and current is small. There have been many attempts to devise a rudder system that has more propulsive power than a conventional rudder. Specially made rudders may be articulated in some fashion and/or have some sort of flexible section near the trailing edge, presumably to work like a fishes tail. Some of those will actually work under limited circumstances, say fly fishing or something like that.

 

One oar boat types give directions on it.

http://www.votenader.org/

http://www.simplicityboats.com/ScullYulohaboat.htm

http://councill.home.mindspring.com/sbjournal/sculling/scull1.

These tell you about the method.