Chimborazo has a circumference of and a diameter of . The ratio of the circumference to the radius varies near the Euclidean value. This has to be factored by the width (circumference) of the valve throat. The ring can be approximated as a circle with circumference l. A nomogram based on height, weight and arm circumference may be used. Or, equivalently, as the ratio of the circumference to twice the radius. Lake Manasarovar is relatively round in shape with the circumference of . His measure of 240,000 stadia translates to , close to the actual circumference of . The hyoplastron features a large number of spines projecting around the circumference. With the permitted circumference between and weight between . The island measures in circumference and covers . Etna covers an area of with a basal circumference of . I-485 has a total circumference of approximately . He is credited with being the first person to measure the Earth's circumference. He was the first to calculate the Earth's circumference (within 0.5 percent accuracy).