Morley's Chess

In 1947, F. V. Morley invented this variant, and wrote about this variant, in a book titled My One Contribution to Chess. The description here is based on the information in Pritchard's Encyclopedia of Chess.

The game is played on a board, with at each of the four sides, a corridor of six squares added. The opening setup is otherwise unchanged.

The rule description is unclear on where pawns promote. To keep as close as possible to orthodox chess, one can promote pawns on the squares where in opening setup the opponents non-pawn pieces are located. Other rules are as in orthodox chess. Pawns can get stuck in a corner, where there only hope of moving is taking a hostile piece.

Another variant

Another variant on a board with enlarged sides is also attributed to Morley. Here, the board has the following shape (displayed with opening setup.)

Again, pawns stuck in a corner can only hope to escape by taking a hostile piece.