exercise for perfect connexion of the hemispheres by connecting both 5th fingers in cross-over-hand-position:

Exactly the passage from a to c1 is with the right 5th finger onto the left 5th finger in the cross-over-position.
exercise for perfect connexion of the hemispheres by connecting both 5th fingers in cross-over-hand-position:
Exactly the passage from a to c1 is with the right 5th finger onto the left 5th finger in the cross-over-position.