Illustrated Companion to the Latin Dictionary/Trigonum

This article incorporates text from a publication now in the public domain: Rich, Anthony (1849). The illustrated companion to the Latin dictionary, and Greek lexicon. p. vi. OCLC 894670115. https://archive.org/details/illustratedcompa00rich. 

TRIGO'NUM (τρίγωνον). A triangular piece of marble, tile, or some artificial composition, used for inlaying patterns in a mosaic pavement of the class termed sectile (Vitruv. vii. 1. 4. PAVIMENTUM, 2.), as shown by the border round the four sides of the illustration (Trigonum/1.1), which represents a piece of pavement on the threshold of the principal entrance to one of the houses at Pompeii.

2. A musical instrument of triangular form, with all its strings of the same thickness, but of unequal lengths (Plat. Rep. 399. C. Soph. Fragm. 361. Athen. iv. 77. Ib. 80.), and which, it is to be inferred from the figure on the left side of the illustration (Trigonum/2.1), copied from a Pompeian painting, was carried on the shoulder when played. The word does not occur in the present sense in any of the extant Latin authors; nor is it clear whether they, or the Greeks, made use of the same term to designate our triangle, which seems probable, since that instrument was not unknown to them, as is proved by the figure on the right side of the engraving, copied from a marble bas relief formerly belonging to the Giustiniani family at Rome, upon which a party of several females are represented playing upon different musical instruments  — the triangle here introduced, the rattle termed crotalum, the tympanum, or tambourine, and the double pipes, or tibiae pares.

• 
  Trigonum/1.1
• 
  Trigonum/2.1