A useful scale for playing in the third position is the Dorian scale or mode. Its degrees are 1, 2, b3, 4, 5, 6 and b7. It is shown below as the D dorian scale, which can be played on the C harmonica.
Here is the D dorian scale played first in the higher octave between holes 4 and 8, and then in the lower octave down to 1. As you play this scale, mentally name the scale degrees, remembering that D is the keynote instead of G.
Written below are two traditional songs played in the third position. Both of them are derived from the dorian scale.