(obsolete) A child's hornbook for learning the alphabet. 1802, William Hutton, The History of the Roman Wall, preface You will also pardon the errors of the Work, for you know I was not bred to letters; but, that the battledore, at an age not exceeding six, was the last book I used at school. (obsolete) A bat or beetle used in washing clothes.
The parachute, like the helicopter and the hang glider, dates back to the drawings of mankind's greatest public genius, Leonardo da Vinci.
Canvas, Silk and Nylon. The canopy of the parachute was initially made of canvas, which was eventually replaced by silk, which was thinner, lighter, stronger, fire resistant and easy-to-fold. In late 1930s and early 1940s, the World War affected silk import in the United States.