Write a brief note on the Spinning Jenny.

The spinning jenny is a multi-spool spinning wheel. It was invented in 1764 by James Hargreaves, in the north west of England. The device dramatically reduced the amount of work needed to produce yarn, with a single worker being able to work eight or more spools at a time. The spinning jenny was so effective in increasing the efforts of a worker's labor that Karl Marx cited it as the cause behind the elimination of slavery.