the.com/circulation
your blood runs a 60,000-mile loop daily and never once asks for a break
means the movement of something around a system or community — blood through the body, air through a room, money through an economy, or copies of a publication among readers.
from From Latin 'circulatio,' from 'circulare' (to form a circle), rooted in 'circulus,' a little ring or hoop — itself a diminutive of 'circus,' a circle or ring. The word entered English in the 1500s as a term for moving in a circle, and it was William Harvey's groundbreaking 1620s work on blood that fixed the now-familiar sense of fluid looping endlessly through the body. The financial and journalistic uses — money and newspapers passing from hand to hand — followed by extending that same image of things going round and coming back.
- total length
- vessels span roughly 60,000 miles, twice Earth's circumference
- daily volume
- heart pumps about 2,000 gallons every day
- discovery
- William Harvey proved the loop in 1628
- full lap
- a blood cell circles your body in under a minute
- capillary width
- some are narrower than a single red cell
gulf stream — warm ocean current transporting 30 million cubic meters of water per second from the gulf of mexico to the north atlantic
thermohaline circulation — global ocean conveyor belt driven by temperature and salinity differences, completing one full cycle every 1,000 years
hadley cell — atmospheric circulation pattern between the equator and 30° latitude responsible for trade winds and desert formation