According to T.S. Ashton and several other historians, the beginning of the era that ended in the 1850s is marked by the invention of Hargreaves' spinning jenny in the 1760s. The precise dates are not universally accepted, though.
In the United States, the industrial revolution lagged after Great Britain; the transition from agricultural to industrial society in the US started with first industrial mill opened by Samuel Slater in 1790. The industrial revolution transitioned to its second phase, the so-called technological revolution or the second industrial revolution with the invention, in 1851, and patent, in 1855, of the Bessemer process. The second industrial revolution lasted until WWI started in 1914.
