Key Out of Time (Time Traders Series #4)

Key Out of Time is a classic science fiction novel written by Andre Alice Norton and first published in 1963. Ross and Arthur are helped by Karara and two trained dolphins in Hawaika, which was settled by Hawaiian and Polynesian settlers. The planet Hawaikan is a warm tropical planet that is mostly ocean. It is so different from what they had expected that they decide to risk a time trip back in the planet's history. Just as they are about to use the time gate a storm blows up and Murdock is flung through the gate and into the planet's past. The time gate is destroyed and Murdock is left to cope with this different and alien world on his own.