Averaging . . . geometry of the center

Perhaps partly due to his experience as an Air Force pilot during World War II,  Harold Nemerov (1920 - 1991) uses geometry with deft precision as he describes phenomena around him.  Here is a poem inspired by a 1986 news item.

Found Poem     by Howard Nemerov 

           after information received in The St. Louis Post-Dispatch, 4 v 86

The population center of the USA
Has shifted to Potosi, in Missouri.

The calculation employed by authorities
In arriving at this dislocation assumes

That the country is a geometric plane,
Perfectly flat, and that every citizen,