Kathleen Schlesinger, 1911 Encyclopædia Britannica, Volume 17… (1911)
“ The strings are twanged by means of a plectrum or pick, held between the thumb and first finger of the right hand. In order to strike a string the pick is given a gliding motion over the string combined with a down or an up movement, respectively indicated by signs over the notes. In order to sustain notes on the mandoline the effect known as tremolo is employed; it is produced by means of a double movement of the pick up and down over a pair of strings. ”
