On the Lighter Side:It was invented by the Roman philosopher Radius Gyrus, some time around the second Century AD. Prior to that time, the earth did not spin, leading to extended darkness in many places, rampant insomnia in others, and temperature extremes almost everywhere.
The eruption of Pompei in 76 AD was the last straw. Romans who had invested in prime seaside real estate there saw the value of their portfolios shrink to bupkes, as the hot sulfur and ash of the volcano added to the constant direct sunlight, and the resort hotels began receiving cancellations by the thousands.
The nation's great thinkers appealed to its scientists to "do something". Within months, Gyrus and his team of researchers and engineers proved the feasibility of their plan to install an axis of symmetry through the earth, and to start the globe rotating on it, thus evenly distributing both the temperatures and the hours of daylight and darkness, uniformly and equitably, to all the inhabitants thereof.
By continuously deploying hundreds of excavation crews to the poles ... each of which periodically relieved both themselves and the crew who had gone before them ... the axis, along with its bearings, was installed within three years. It is an historic testament to the value of project management and planning that only once during the entire operation was there a delay, when one unfortunate crew chief named Vas Deferens, upon arriving on site, opened the box of balls which he had been tasked to deliver and discovered that he had lost his bearings.
Finally, with the axis completed, beginning slowly and building to a crescendo, the globe was spun up to its final angular velocity of nearly 4.4 milliradians per minute, where it remains to this day, with only negligible deceleration through the centuries that have intervened.