George Duke wrote on Mon, Apr 7, 2008 04:51 PM UTC:
We started this thread with the following, then went through some exotic
pieces reported by Martin Gardner decades ago, covered other topics,
whereupon discovering 'The Turk' (2002), are still absorbing Tom
Standage's last chapters relating it all to computer dominance today by
such as IBM's Deep Blue. >>> ''World's first binary computer?
Chessboard 64-square uses Rook & Bishop moves [Add. algorithm: depict
each number across a rank by 'R' counters, then use Rook moves to slide
all the representations to Rank 1; right to left, replace 'doubles' by 1
a___b___c___d___e___f___g___h to left until each first-rank square
___ ___ ___ ___ ___ ___ ___ is binary 1 or 0, where a 'Rook' is '1'.
___ ___ ___ ___ ___ ___ ___ Bishop-like Multiplication to left shows
___ ___ ___ ___ ___ ___ ___ chess-computer-abacus 19x13 (differing
___ ___ ___b___ ___ ___b___b 1 procedure than Addition). After place-
___ ___ ___b___ ___ ___b___b 1 ment, Bishop-counters are to move dia-
___ ___ ___ ___ ___ ___ ___ gonally left downward. Moves become B d4-
___ ___ ___B___ ___ ___B___B 1 a1, B d3-b1, g4-d1, g3-e1, h4-e1, h3-f1,
128 64 32 16 8 4 2 1 making first rank now:
B B BB BB B B B And again replacing the 'doubles' with
one to each pair's adjacent left: BBBB_BBB = 11110111 = 247 (Base 10).
--Method of John Napier (1617) 'Rabdologia', including also Subtraction,
Division and Extracting Roots on 64-square chessboard, Sc. Amer. 1985.''