Most weeks groups of visitors come to Loughborough to witness the casting of new bells – often bells for their own parish church. They stand safely on the viewing gallery in the casting hall well above the floor of the foundry where the bells are to be cast. The roar of the furnace ceases as the melting of the metal stops, and then the warmed crucible is placed beneath and the moulten bell metal pours into it. And at this point the ancient ritual of purging the metal using a large branch from a willow tree provides a most unusual spectacle.
This vital part of the process has been passed down through generations of bell founders from Mediaeval times. The willow has salicylic acid in its sap, (also used as a a painkiller in asprin) and this purges the metal and de-gases it of hydrogen and oxygen. So this natural product has been used for many centuries, and continues in use today!