Sound.
（Surgical.) (Fr. Sonde, a canula or director.) A long instrument (a b, Fig. 5319), usually of metal and partaking of the nature of a probe. Used especially in making explorations in the bladder in search of stone. It is inserted through the urethra, and a peculiar click is heard when it comes in contact with stone. c is Skene's uterine sound. The end of the probe being in contact with the fundus, the section having a button on the end is projected telescopically until it comes in contact with the cervix, and the distance from the button to the end of the sound is the length of the womb. Leaden sounds are used to follow the curved path of a glancing ball. See probe. Sonde de Anel; a silver stylet with awl-point, used in probing the lachrymal passages. Sonde de Belloc; an instrument for plugging the nasal fossae in cases of hemorrhage. A curved silver canula, open at both ends, and furnished with a button, to which the epistaxis plug is attached, and with which the posterior nostril is stopped. Sonde Brisee: a probe in two sections, which screw together. It is blunt at one end, and has an eye at the other, so as to be used as a probe or seton needle. Sonde a Conducteur; a guide for a catheter. It is introduced in company with a catheter of small size, open at the beak. The catheter being withdrawn, leaving the Sonde in position, the latter acts as a director in introducing a larger catheter. Sonde de Saforest; a small nasal probe, or crooked canal, for throwing injections. Sonde, or Pincers of Hunter: a silver canula, containing a wire, which is fenestrated, and has a pair of scoops which spring apart as they emerge from the beak of the canula, and by retraction clasp calculi in the urethra.
