5 sols, but only exchangeable for assignats (practically worthless notes) Wiki entry:- Les Frères Monneron was built up in England by Matthew Boulton, thanks to the steam engine of James Watt, producing 2 and 5 sols coins in great quantities in the Soho factory in Birmingham from the end of 1791. Watt's steam engine.necessity money eased the coinage shortage then current in France and their technical and aesthetic quality was much superiour to mediocre base metal issues produced by official sources. In March 1792, the Monnerons went bankrupt and Pierre fled. His brother Augustin took over the business, but a law of 3 May 1792 forbade the production of money by private concerns. In September a decree forbade the commercialisation of confidence-coins. These necessity coins were in circulation until the end of 1793. These pieces of