Article #7 - Circumferance (sic) of the earth

How was the circumferance [sic]

of the earth first ascertained.

             I have not succeeded in finding out to a certainty...

[The unnamed writer goes on to explain two possible methods: one, by calculating from the convexity as seen at a measured distance in the ocean and then using geometry to arrive at the answer; and two, “by ascertaining the time the sun is in passing over any measured space on the equator” and calculating from that.]

            ...There may be other methods of ascertaining the circumferance of the earth, these appear to be two of the most simple but whether the earth was first ascertained by either of these  methods or not I cannot say.