Crompton was born near Bolton, England, in 1753. His father died when he was five, and he learned at an early age to help his mother with all the household tasks. Among these was working with a spinning jenny, the yarn from which was sold at a local market. Crompton's mother was a stern woman with a short temper, a temper which flared every time the jenny broke its yarn. Realizing this was the fault of a flaw in the jenny's design, Crompton set out to construct his own spinning machine.
The building of the spinning mule took five years and all the money Crompton had earned as a fiddler at a local theater. He worked in secrecy, usually at night; the noises coming from his workshop led many neighbors to believe the building was haunted. The final product--crude, but very efficient--was finished in 1779, just after Crompton's twenty-seventh birthday.
The spinning mule used the two most important elements of the water-frame and the spinning jenny. From Arkwright's water frame it borrowed a set of rollers to draw out the cotton fibers; from the jenny, a moving carriage that gently stretched the roving. Added to this was Crompton's own spindle carriage, which insured that no tension was applied to the yarn before it had been completely spun. The yarn spun by this machine was strong and smooth, able to be used in materials such as muslin, and did not break as easily as that spun by the jenny.