"I certainly would give a year's growth to know whether that is the Nelson," Harry said, as the boys sought the shore and began gathering dry wood, which, it may be well to add, was not easy to find, as there had been quite a shower during the day.  "For all we know," he continued, "there may be another aeroplane here.  If the people who are trying for the Lyman concession are as active here as they seem to have been in Paraguay, they may have half a dozen airships out after the Nelson."