Semantron

The semantron or semandron (Greek: σήμαντρον), or semanterion (σημαντήριον), also called a xylon (ξύλον) (Romanian: toacă; Russian: било, bilo; Bulgarian, Macedonian and Serbian: клепало, klepalo) is a percussion instrument used in monasteries to summon the monastics to prayer or at the start of a procession.

The instrument comes in three chief varieties: a long wooden plank held in the player's left hand and struck with a wooden mallet in the right; a larger, heavier, fixed timber block suspended by chains and struck by one or two mallets; and a fixed metal variety, often horseshoe-shaped and struck by a metal mallet.

The portable semantron is made of a long, well-planed piece of timber, usually heart of maple (but also beech), from 12 feet (3.7 m) and upwards in length, by 1 ¹⁄₂ feet (46 cm) broad, and 9 inches (23 cm) in thickness. Of Levantine and Egyptian origin, its use flourished in Greece and on Mount Athos before spreading among Eastern Orthodox in what are now Bulgaria, Romania, Moldova, Serbia, Montenegro, Bosnia and Herzegovina and the Republic of Macedonia. It both predates and substitutes for bells (first introduced to the East in 865 by the Venetians, who gave a dozen to Michael III), being used to call worshipers to prayer. The metal variety is made of iron or brass (ἁγιοσίδηρα, hagiosidera / клепало, klepalo); formed of slightly curved metal plates, these give out a sound not unlike that of a gong.

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