Tachymeter
This feature is found on watches that are made for speed measurement. The tachymeter scale is located on the case top ring or inner dial
ring. It can be used to measure speed in miles per hour, knots, or kilometers per hour, using the scale on the ring.
Example of usage:
In a driving race, the car passes the first mile (km) post when the seconds hand is at the 12:00 position (60 seconds mark). Commence
measurement. At the 40 second mark the car passes the second mile (km) post, you will see that the car traveled a distance of one mile at
90 miles (km) an hour.
