Thanks, Mike! Interesting that I called it cylinder chess; perhaps I once heard about it long ago & merely forgot. The wiki article indicates that K+R can't always beat K in cylinder chess, which is kind of interesting. I assume that someone has actually proved this? The other article at chessvariants.org indicate that cylinder chess is usually played with the board rotated by 4 positions, to better focus on the doubled rooks (now in the center). It also indicates that cylinder chess is _more fun_ than regular chess, as the game develops much faster. I also like the ability of some pieces to provide double checks. I wonder what the relative value of the pieces are in cylinder chess? The articles seem to indicate that bishops & queens get more powerful, at least relative to pawns & knights. Other than providing a "book", it shouldn't be very difficult to modify an existing chess program to play cylinder chess. I wonder if any of the existing programs have this as an option? At 11:56 AM 2/10/2012, Mike Stay wrote:

http://en.wikipedia.org/wiki/Cylinder_chess http://www.chessvariants.org/historic.dir/byzantine.html http://www.3manchess.com/

On Fri, Feb 10, 2012 at 11:41 AM, Henry Baker <hbaker1@pipeline.com> wrote:

...

In thinking about "continuous" chess, I started thinking about pawn lines as a continuous line across a board of width 8 units. I then started thinking about Fourier transforms of that line, and it seemed natural to paste the left chess board boundary to the right one (without a twist!) -- hence a cylindrical chess board. (It makes a lot less sense to consider a toroidal chess board for a number of reasons.)

I think thought -- let's go back to the "regular"/discrete chess board & consider a cylindrical board with the left & right boundaries pasted together.

What do the chess moves look like?

Pawns on either the left or right boundary can attack the other boundary.

Bishops' diagonal lines extend beyond the left & right boundaries & continue on the other side.

Knights aren't trapped next to the left & right boundaries, but can jump across them.

A rook can attack a piece from both sides, if it and the other piece are the only ones on its rank!

A Queen can also attack from both sides on its rank, as well as follow diagonals like bishops.

A King can't be pinned against one of the sides of the chess board, although it can still be pinned against the top or the bottom.

Q: Is cylindrical chess still pretty even for white & black?

I can imagine that the answer is still yes, because while all the pieces have a bit more freedom, so does the King, so it is harder to trap him.

Perhaps there would be a larger number of draws?