Skookum, cultus, hyack, saltchuck, klahowya, tillicum: It is in words like these that the last vestiges of a lost British Columbian language remain. It was known as "Chinook." Its use today is mainly confined to colloquialisms, and place names like Boston Bar, Canim Lake, Illahee Mountain, Snass Creek, and Skookumchuck. It began as a trading jargon, but it soon evolved into a distinct West Coast tongue. Down through the years, as many as a quarter...