Magnet »I love Bach«
The seal which Johann Sebastian Bach used in his letters after 1720 consists of three letters J,S & B. These letters are normal and mirror-inverted arranged that it looks like an ornament. You can find one big reproduction of the seal at one of Bach’s old chests which is stored in the Bach Museum Leipzig.
That is one of the reasons why this seal takes part in the Logo of the Bach-Archiv Leipzig.