This phrase comes from steam engines.

这个表达来自蒸汽。

See How Steam Engines Work for more information.

更多信息见蒸汽发动机工作原理。

A study that covers everything from plows to steam engines.

一部覆盖了从犁到蒸汽机等任何东西的研究。

Thus, steam engines are not used, produced, or needed anymore.

因此，蒸汽机是不被使用的、不被生产的或不再被需要的。

Steam engines had not yet been invented, nor would they for a long time.

蒸汽引擎还未被发明，并且在很长的一段时期内都不会。