US dollars writing of essay Cullivan said he believed the flat-bottomed cargo boat, called a lighter, came from the California Gold Rush period starting in the late 1840s when hundreds of ships landed in San Francisco Bay with passengers in search of new lives and precious metals. 必須 2000文字以内 [bbs:youtube:(Youtubeの動画ID)]と書くとYoutubeの動画が貼れます。(例:[bbs:youtube:OQThUAQ0UN0])