Twelve spokes, one wheel, navels three.

Who can comprehend this?

On it are placed together

three hundred and sixty like pegs.

They shake not in the least.— Dirghatamas, Rigveda 1.164.48 c. 1500–1200 B.C.

I’m not clever in math. I can notice some basic relationships, though, and I can see that both the 12 hour clock and the 360° circle are divisible by 6’s (and of course, 3’s). On the clock face, the numbers 3, 6, 9, and 12 can be connected with lines to form diamond with a plus sign (+). The plus sign is also a visual representation of four 90° angles – the 360° of a circle or the four interior angles of a square.

Like the numbers on the clock and the degrees in a circle, the Persian calendar 360 day year is divisible by 6’s and 3’s and suggests that the degrees on a circle may be partly a graphical representation of a year. Similarly, our modern calendar is divided, like a clock, into twelve units (months).

Aztec and Mayan calendars also take the form of a circle, and design elements from some of these ancient calendars have been used in modern currency.

Continue reading Circle geometry II: 3, 6, 9