I just re-read the world’s oldest squash books: The Game of Squash (New York: J.F. Taylor, 1901) and Racquets, Tennis, and Squash (New York: D. Appleton, 1903).
Both were written by Eustace Miles, an Englishman. In the first, Miles presciently suggested the possibility of movable walls. He also just raved about the new game: “It would be far more correct to describe Squash as many games in one than as a simple monotonous game that requires no skill or adaptability.”
Later he added: “Actual games of Squash are excellent: nothing can quite take their place, either for recreation and enjoyment, or for social intercourse.”
The second book, 336 pages long, has numerous photographs and ranges across obscure ball games like pelota as well as those in the title. Miles had distinct theories about health including advocating for vegetarianism. He doubted the usual remedy of the time for “staleness,” which was champagne and a large dinner. He explained what he called “self-suggestion” or what we now call visualization. He argued for sleeping in “night-socks” to keep your feet warm.
He loved squash: “it forces itself with irresistible arguments upon him whose ambition is to excel.”
The advice Miles issued in the last paragraph of the book still rings true one hundred and twelve years later: “Use your strongest points in Matches; use your strong and less weak points in practice-games; use your still weaker points in practice [alone] inside the Court.”