The ancient Mexicans possessed a drum which gave forth two distinct tones of definite pitch. It is thus described by Carl Engel in his work on Musical Instruments: 'They [the Mexicans] generally made it of a single block of very hard wood, somewhat oblong square in shape, which they hollowed, leaving at each end a solid piece about three or four inches in thickness, and at its upper side a kind of sound-board about a quarter of an inch in thickness. In this sound-board, if it may be called so, they made three incisions, namely, two running parallel some distance lengthwise of the drum, and a third running across from one of these to the other just in the centre. By this means they obtained two vibrating tongues of wood which, when beaten with a stick, produced sounds as clearly defined as those of our kettledrums.’ In some of these wooden drums the two tongues on being struck at the same time produced a third; in others a fifth; in others a sixth, and in some even an octave. The difference in pitch was obtained by making the two tongues of a different thickness, and naturally the greater the difference in thickness the larger was the interval produced. A curious instance of drums which give forth a sound of a definite pitch is the bamboo drums, still to be found in some of the islands of the Pacific. These drums were first described in the account of Captain James Cook’s third voyage to the Pacific ocean. The whole passage is of exceeding interest, giving as it does a picture of purely primitive musical development untouched and uninfluenced by any civilized suggestion. The date, as far as I have been able to ascertain, was May 18, 1777, and the place Hapace (Hapai) in the Tonga Island group. The account is as follows: 'A chorus of eighteen men seated themselves before us in the centre of the circle composed of numerous spectators, the area of which was to be the scene of the exhibitions. Four or five of this band had large pieces of bamboo, from three to five or six feet long, each managed by one man, who held it nearly in a vertical position, the upper end open, but the other end closed by one of the joints. With this closed end the performers kept constantly striking the ground, though slowly, thus producing different notes according to the different lengths of the instruments, but all of them of the hollow or bass sort; to counteract which a person kept striking quickly, and with two sticks, a piece of the same substance, split and laid along the ground, and by that means furnishing a tone as acute as those produced by the others were grave. The rest of the band, as well as those who performed upon the bamboos, sang a slow and soft air, which so much tempered the harsher notes of the above instruments that no bystander, however accustomed to hear the most perfect and varied modulations of sweet sounds, could avoid confessing the vast power and pleasing effect of this harmony.’