I spend approximately 1.5 hours on a bus most workdays. I recently had an idea of finding an subject of interest and reading about it while on the bus. Topics can vary and I may include any number of links for the subject.
The first subject that I thought of was Horsepower. Specifically, I was curious about the origin of the unit of measurement. For brevity, Wikipedia did not disappoint.
[James] Watt defined and calculated the horsepower as 32,572 ft·lbf/min, which was rounded to an even 33,000 ft·lbf/min.
Of course there is a standard for calculating Horsepower for automobile engines as dictated by the Society of Automotive Engineers (SAE), but I also find it interesting that there are other variations of the Horsepower unit in use. I figured there would be an Imperial and Metric version, but I had no idea there was a “Boiler Horsepower” or a “Tax Horsepower”.