The use of Mathieu’s tonsillotome requires but one hand and one motion.  The middle and index fingers are passed through the double rings, the thumb into the other.  After the fork has been pushed through the tonsil, it rises and draws the gland through the ring, then a catch is lifted and the knife is drawn down, cutting the protruding mass with the same motion of the hand that drove the knife forward.  - 1889 Tiemann