"In 1899, the American drug manufacturer Merck & Co. first published a small book titled Merck's Manual of the Materia Medica. It was meant as an aid to physicians and pharmacists, reminding doctors that "Memory is treacherous." Compact in size, easy to use, and comprehensive, The Merck Manual (as it was later known) became a favorite of those involved in medical care and others in need of a medical reference. Even Albert Schweitzer carried a copy to Africa in 1913, and Admiral Byrd carried a copy to the South Pole in 1929."