The original meter was defined as 1/10,000,000 of the meridian through Paris between the North Pole and the Equator.

• A. The equator
• B. The meridian through Greenwich
• C. The meridian through Paris
• D. The North Pole

Answer: (C)

The unit was anchored to a real length on Earth by using a fraction of the distance along a line that runs from the North Pole to the Equator. That line is a meridian, and the Paris meridian was chosen as the reference. So one meter was defined as 1/10,000,000 of the distance from the North Pole to the Equator along that Paris meridian. This makes the Paris meridian the key reference for the original definition. The equator isn’t a meridian, the North Pole is just an endpoint, and the Greenwich meridian later became the international prime meridian but wasn’t the basis for the original meter.