These are a single and a double blade surgeon's surgical scalpel knifes with curved blades made and signed by John Weiss & Son, London. The blades are of two types: with blunt point and restricted cutting edge, the other with a sharp point. The handle shield is made of high quality tortoise shell. This type of folding Bistourie was used during the 19th century for operating irreducible or strangulated hernias.