Early Chinese records read that tin was one of the Chinese imports into Manila in the thirteenth century.  Copper was mined and wrought by the Igorot when the Spaniards came to the Philippines, and they wrote regarding it that it was then an old and established industry and art.  It may possibly be that bronze was made in the Philippines before the arrival of the Spaniard, but there is no proof of such an hypothesis.

The gong to-day enters the Bontoc area in commerce generally from the north —­ from the Igorot or Tinguian of old Abra Province —­ and no one in the Provinces of Benguet or Lepanto-Bontoc seems to know its source.  Throughout the Archipelago and southward in Borneo there are metal drums or “gongs” apparently of similar material but of varying styles.  It is commonly claimed that those of the Moro are made on the Asiatic mainland.  It is my opinion that the Bontoc gong, or gang’-sa, originates in China, though perhaps it is not now imported directly from there.  It certainly does not enter the Island of Luzon at Manila, or Candon in Ilokos Sur, and, it is said, not at Vigan, also in Ilokos Sur.

In the Bontoc area there are two classes of gang’-sa; one is called ka’-los, and the other co-ong’-an.  The co-ong’-an is frequently larger than the other, seems to be always of thicker metal, and has a more bell-like and usually higher-pitched tone.  I measured several gang’-sa in Bontoc and Samoki, and find the co-ong’-an about 5 millimeters thick, 52 to 55 millimeters deep, and from 330 to 360 millimeters in diameter; the ka’-los is only about 2 to 3 millimeters thick.  The Igorot distinguishes between the two very quickly, and prizes the co-ong’-an at about twice the value of the ka’-los.  Either is worth a large price to-day in the central part of the area —­ or from one to two carabaos —­ but it is quite impossible to purchase them even at that price.

Gang’-sa music consists of two things —­ rhythm and crude harmony.  Its rhythm is perfect, but though there is an appreciation of harmony as is seen in the recognition of, we may say, the “tenor” and “bass” tones of co-ong’-an and ka’-los, respectively, yet in the actual music the harmony is lost sight of by the American.

In Bontoc the gang’-sa is held vertically in the hand by a cord passing through two holes in the rim, and the cord usually has a human lower jaw attached to facilitate the grip.  As the instrument thus hangs free in front of the player (always a man or boy) it is beaten on the outer surface with a short padded stick like a miniature bass-drum stick.  There is no gang’-sa music without the accompanying dance, and there is no dance unaccompanied by music.  A gang’-sa or a tin can put in the hands of an Igorot boy is always at once productive of music and dance.

The rhythm of Igorot gang’-sa music is different from most primitive music I have heard either in America or Luzon.  The player beats 4/4 time, with the accent on the third beat.  Though there may be twenty gang’-sa in the dance circle a mile distant, yet the regular pulse and beat of the third count is always the prominent feature of the sound.  The music is rapid, there being from fifty-eight to sixty full 4/4 counts per minute.