Jenny Lind was the first of a class of ten steam locomotives built in 1847 for the London, Brighton and South Coast Railway (LB&SCR) by E. B. Wilson and Company of Leeds, named after Jenny Lind, who was a famous Swedish opera singer of the period.

[1] Joy had spent his formative years studying all the locomotives he came across, sketching them, making notes, and interviewing their owners and crews — and, if he could, getting rides on them.

There is a limit to the rate that steam can be delivered to the pistons; therefore, higher speed was obtained with larger driving wheels.

Joy and Fenton settled on a medium-sized boiler, 800 sq ft (74 m2) heated surface area, with a pressure of 120 lbf/in2 (827 kPa) and concentrated on its steaming abilities.

Indeed, the manufacturers charged a hefty premium for variations, although in response to pressure, they later built a number of "large jennies".

John Chester Craven, Kirtley's successor at Brighton, built a class of five similar "Jenny Lind singles" from 1853 to 1854.