Leigh Mercer

Leigh Mercer (1893–1977) was a British writer of wordplay and recreational mathematics who is best known for devising the palindrome "A man, a plan, a canal: Panama!".

Word Ways called him "a luxuriant source of verbal exotica and linguistic curiosa." Among his palindromes are "Sums are not set as a test on Erasmus." In 1946, he came up with "Plan a canal p" which he admitted was "not very hopeful looking" though it became "A man, a plan, a canal: Panama!".

This is read as follows: A dozen, a gross, and a score Plus three times the square root of four Divided by seven Plus five times eleven Is nine squared and not a bit more.