The strings of the hammered dulcimer are often tuned according to a circle of fifths pattern. Typically, the lowest note (often a G or D) is struck at the lower right-hand of the instrument, just to the left of the right-hand (bass) bridge. As a player strikes the courses above in sequence, they ascend following a repeating sequence of two whole steps and a half step. With this tuning, a diatonic scale is broken into two tetrachords, or groups of four notes. For example, on an instrument with D as the lowest note, the D major scale is played starting in the lower-right corner and ascending the bass bridge: D – E – F – G. This is the lower tetrachord of the D major scale. At this point the player returns to the bottom of the instrument and shifts to the treble strings to the right of the treble bridge to play the higher tetrachord: A – B – C – D. The player can continue up the scale on the right side of the treble bridge with E – F – G – A – B, but the next note will be C, not C, so he or she must switch to the left side of the treble bridge (and closer to the player) to continue the D major scale. See the drawing on the left above, in which "DO" would correspond to D (see Movable do solfège).