Complex sentence: In 1882 he discovered "Emerald Lake" which name lasted until 1884 when the name was changed to Lake Louise in honour of Princess Louise, wife of the governor general, the Marquess of Lorne Campbell.
Split into simpler sentences: In 1882 he discovered "Emerald Lake" which name lasted until 1884. The name was changed to Lake Louise in honour of Princess Louise, wife of the governor general, the Marquess of Lorne Campbell.