apr 9, 1769 - James Watt developed the steam engine
Description:
Although the steam engine was already technically invented, a Scottish man Watt developed it even more and registers as an official patent. They might not of realised it, but this changed the world as we know it.
The original steam engine was just the bare basics, used for mining. His updates to the machine improve it in almost every way, including power, speed and cost.
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Patrick HASS timeline
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