Complex sentence: He served as the Principal of Carthage High School in Carthage, Mississippi in 1889 and 1890 and of the graded schools of Kosciusko, Mississippi from 1890 to 1892.
Split into simpler sentences: He served as the Principal of Carthage High School in Carthage, Mississippi from 1889 to 1890. He then served as Principal of the graded schools in Kosciusko, Mississippi from 1890 to 1892.