Samuel Loyd (January 31, 1841 - April 10, 1911) was an American puzzle author and recreational mathematician.

Loyd popularized and is usually credited with the invention of the fifteen puzzle. He also authored a number of chess problems, often with witty themes. Following his death, his book Cyclopedia of Puzzles was published (1914).

An enthusiast of Tangram puzzles, Loyd published a book of seven hundred unique Tangram designs and a fanciful history of the origin of the Tangram. Europe and America were experiencing a Tangram craze at the time, and Loyd's popular book earned him a significant amount of income.

Contents

1 Excelsior problem 2 Books 3 See also 4 External links

Excelsior problem

One of his best known chess problems is the following, called "Excelsior" by Loyd after the poem by Henry Wadsworth Longfellow. White is to move and checkmate black in five moves against any defense:

Loyd bet a friend that he could not pick a piece that didn't give mate in the main line, and when it was published in 1861 it was with the stipulation that white mates with "the least likely piece or pawn".

Books

• Sam Loyd's Book of Tangram Puzzles (ISBN 0486220117): by Sam Loyd
• Mathematical Puzzles of Sam Loyd (ISBN 0486204987): selected and edited by Martin Gardner
• More Mathematical Puzzles of Sam Loyd (ISBN 0486207099): selected and edited by Martin Gardner
• The Puzzle King: Sam Loyd's Chess Problems and Selected Mathematical Puzzles (ISBN 1886846057): edited by Sid Pickard

See also

• Henry Dudeney

External links

• Biography from the School of Mathematics and Statistics website at the University of St Andrews
• The Sam Loyd Cyclopedia of Puzzles - The complete 1914 book by Sam Loyd (public domain)
• Farmer and Wife to Catch Rooster and Hen - interactive Sam Loyd's puzzle