Baines and Onedin find an uncharted island,rich in guano,which they intend to mine without telling anybody. However,Matt Harvey learns about it and sets sail in a Frazer Line ship but fails to locate the island. Instead he returns with valuable whale-bone and claims that the guano was too acidic for use. Elizabeth believes she has got one over on her brother until she discovers that he already knew this fact. (thetvdb.com)