100 Französische Franken = 20 Fünf Franken Thaler

The Bank in Basel was one of several cantonal private banks operating before the Swiss National Bank's founding in 1907, each issuing its own notes with no federal coordination. This denomination — expressed as both 100 French Francs and 20 Five-Franc Thalers simultaneously — reflects the genuinely chaotic monetary arithmetic of mid-19th century Switzerland, where multiple foreign currencies, local coins, and bank notes circulated interchangeably and conversion between them was a daily practical necessity, not a formality.

The dual denomination inscription was a functional requirement, not decorative. Basel's commercial ties ran north into Germany and west into France with equal intensity.