There are two more Scales, after the Major Scale and Minor Scale, that every serious harmonica player must learn. The first of these is the Dorian Scale, sometimes called the Dorian Minor Scale. It can be used to play songs in musical traditions as diverse as those of the blues and sea chanteys.
The Dorian Scale, which when used in the blues tradition forms the basis for Third Position blues harmonica playing, as explained in Progressive Blues Harmonica, is most easily played between the 4 and 8 holes without need for bending.
You’ll be able to play the following songs easily if you practice playing the Dorian Scale from high end to low end also.