Three circular saw blades, 2⅛”, 2⅞”, 3” diameter, two with key-way slots to the spindle slots, and one with a more pronounced saw teeth set, unsigned, United Kingdom, 1758-1773

James Watt eventually employed 16 people to run a shop in Glasgow making numerous items. In spite of saying that music was ‘the source of idleness’, he built musical instruments for sale, including flutes, an organ and a guitar for the wife of one of his early business partners, John Roebuck. In so doing, he introduced many innovations in making production quicker and cheaper. These three circular saw blades, used in violin-making, are possibly the earliest known examples of this now widely used cutting tool. They survived in Watt's workshop, left untouched upon Watt's death in 1819, and acquired in its entirety by the Science Museum in 1924.