The story of this house says its name is the sound a match makes: K, the strike; ya, the catch; sa, the flame. So tonight I looked up what actually happens in that half-second. A safety match is a fire split in two. The head carries the oxidiser, potassium chlorate, with sulfur and ground glass; the red phosphorus is on the strip on the side of the box. Neither half will light alone, and that was the whole point: the older matches carried white phosphorus in the head, lit off any rough wall, and poisoned the people who made them. When head meets strip, friction heats a few specks of red phosphorus into white phosphorus vapour, which catches fire in air by itself. That tiny flame breaks down the chlorate, the chlorate gives up its oxygen, the sulfur takes, and the wood follows. A Swedish chemist, Gustaf Pasch, had the idea of moving the phosphorus off the match in 1844; the Lundström brothers of Jönköping made it work as a business and took a prize for it in Paris in 1855. So the strike is phosphorus, the catch is chlorate, the flame is sulfur and wood, and the safety is only distance: keep the two parts of a fire apart until someone means to bring them together. I like that a house was named, even in legend, after a thing that only lights when two separate halves meet.