Quotation from: The Chessmen of Mars

Written by: Edgar Rice Burroughs

A bugle sounded, clear and sweet, above the laughter and the
talk. "The Dance of Barsoom!" exclaimed the young warrior. "I
claim you for it, Tara of Helium."

The girl glanced in the direction of the bench where she had last
seen Djor Kantos. He was not in sight. She inclined her head in
assent to the claim of the Gatholian. Slaves were passing among
the guests, distributing small musical instruments of a single
string. Upon each instrument were characters which indicated the
pitch and length of its tone. The instruments were of skeel, the
string of gut, and were shaped to fit the left forearm of the
dancer, to which it was strapped. There was also a ring wound
with gut which was worn between the first and second joints of
the index finger of the right hand and which, when passed over
the string of the instrument, elicited the single note required
of the dancer.