John Henderson was much admired in the latter half of the eighteenth century for his incredible memory. His skills were tested by a Professor Dugold Stewart. In his presence, Henderson took up a newspaper, and after reading it once, repeated each portion of it by heart. Professor Stewart was amazed. Henderson said modestly: "If you had been like me - obliged to depend during many years for your daily bread on getting words by heart, you would not be so astonished at habit having produced this facility."