Complex sentence: In 1860, Sir Hugh Allan purchased fourteen acres on the slopes of Mount Royal for $10,000 from the estate of the late Simon McTavish, then considered in the countryside, outside the confines of Montreal.
Split into simpler sentences: In 1860, Sir Hugh Allan purchased fourteen acres on the slopes of Mount Royal, for $10,000 from the estate of the late Simon McTavish. The property was then considered in the countryside and was outside the confines of Montreal.