Playing in third position is violinists’ second favorite thing to do (after first position)! It’s a “handy” position to find; your hand feels very comfortable on the neck of the violin. An added advantage to third position is that finger 1 plays exactly an octave above the next-lower string, so the outer edge of your palm (just under finger 4) is very near to, or just touching, the body of the violin.
For third position, you need to put your first finger on the spot where the third finger normally plays in first position. If you use the same idea that you use to prepare for second position you start out with the following moves:
You take just one more step to arrive at the fourth position. Although third position gets all the attention, finding fourth position is just as easy, because as you look down the “telescope” of your strings, your first finger plays the same note as the adjacent open string to the right. For example, if you play in fourth position on the A string, your first finger matches the E of your open E string.