Clay was a midshipman who served aboard the frigate HMS Lydia.

Around the time the Lydia left England, the teen-aged Clay's voice was beginning to deepen, alternating between squeaking and croaking. As his captain, Horatio Hornblower, noted, by the time the Lydia was nearing the Gulf of Fonseca, he had learned to use it "properly".

Clay was killed in action aboard the Lydia.