Diverse themes here! Two notes feature famous personalities with connections to the city, including the very famous Romantic author and poet Clemens Brentano. Sketches of the castle on the Rhein grace three of the notes, while the remaining two feature cartoons, each with a little comic verse. One is written in standard High German, and reads: "Too expensive is now wine and liquor, now we only drink Dähler spring!"
Robert Ball Nachf. in Berlin (the Nachf. stands for Nachfolger which means 'successor(s)') is one of the big numismatic mail-order and auction houses of the 1920s, and they are one of just a few Notgeld dealers from the Notgeld era who actually printed their own envelopes with information about the set contained inside. Some are handwritten, others are typed or mimeographed, and some are even specially printed for the particular note or set that's inside. The envelopes have become quite rare, especially in excellent condition, much rarer than many of the original envelopes that accompanied the sets - to the point that trying to find any particular Robert Ball envelope is usually a lost cause. The company assigned their own catalog numbers to the notes, printed in the upper right-hand corner of each envelope.