The side drum, or “snare drum,” is the military drum. It is used, however, in the Orchestra for many rhythmic effects. The cylindrical “shell” is of brass; and at each end is a parchment “head,” held down by a small hoop, which is, in its turn, held in place by a still larger hoop. Cords with leather tags keep the “heads” taut. The upper head, on which the drummer plays, is called the “batter head.” The lower one is called the “snare head.” Across the “snare head” the “snares” are laid. These are thin strings of catgut, something like violin strings, and they are stretched back and forth from nuts to screws. They have to be screwed down rather tightly. There may be two or three “snares” only and there may be a dozen. [Illustration: KETTLEDRUMS, SYMPHONY SOCIETY OF NEW YORK _Karl Glassmann_] When the player hits the “batter head,” the vibrations start others in the air that is inside the shell. These internal vibrations excite the “snare head” and then the “snares” begin to rattle. Consequently, a great racket is set up, which might be described as a peculiar “crackling” tone. The “side drum” is a very hard thing to play well. The technique is not founded on a single stroke, but on a double alternate stroke with each hand. It is played with a wooden drumstick in each hand. In the roll, called the “Long Roll,” or “Daddy Mammy,” the drummer strikes the “batter head” left-left, right-right, left-left, right-right and so gets a kind of rebounding stroke. In addition to the roll, there are two other strokes: the _flam_, a short note before a longer one; and the _drag_, a sort of roll preceding a note—buddledee DUM! buddledee DUM! THE BASS DRUM The bass drum is a large wooden shell, like a big cylinder over both ends (or “heads”) of which parchment (or skin) is stretched. This parchment is held down by hoops. The player loosens, or tightens, these “heads” by means of an arrangement of leather braces and tags working on a cord that is zigzagged around the cylinder. The bass drum is struck with a stick ending in a soft, round knob. The bass drum may be used for noisy moments to imitate the firing of guns and the roll, or crash, of thunder and also to mark _crescendos_ and climaxes. If played very softly, it is solemn and awe-inspiring. The bass drum always stands sideways. The larger the drum, the more sonorous are the sounds. THE TRIANGLE The Triangle is a steel rod bent in a three-sided shape and left open at one angle. It is about seven inches each way and not quite an inch thick. It is hung by a string at the upper angle. This string the performer holds in his fingers so that the triangle hangs loosely. The performer hits the instrument with a small spindle-shaped bar of steel, called a “beater.”