Complex sentence: Martin was employed as a writing teacher, initially working at Burton-on-Trent in 1798, then in Buxton and finally in 1805 he moved to Macclesfield where he taught at Macclesfield Grammar School.
Split into simpler sentences: Martin was employed as a writing teacher, initially working at Burton-on-Trent in 1798, then in Buxton. Finally, in 1805, he moved to Macclesfield, where he taught at Macclesfield Grammar School.