Complex sentence: The dome originally had a naked statue of Mercury on the before it was removed in the 1920's with reasons given that it was either unstable in poor weather or viewed as sinful by residents.
Split into simpler sentences: The dome originally had a naked statue of Mercury on thetop of it before it was removed in the 1920's. The reasons given for removal were either because it was either unstable in poor weather or viewed as sinful by residents.