The Medial S
She fays that "Congrefs" would be written with both medial and round "s". Her article also says that the integral sign comes from the media "s", for "sum".
The medial S is most often seen in 2020 on the label of Jagermeister liqueur bottles.
"The paragraph mark ( ¶ ) is used when citing documents with sequentially numbered paragraphs (e.g., declarations or complaints). The section mark ( § ) is used when citing documents with numbered or lettered sections (e.g., statutes). § The paragraph mark is also known as a pilcrow ."