The official full-power coal-consumption trial of H.M.S. Earnest (length 213 feet, beam 21 feet 6 inches, draught 9 feet 9 inches; displacement 355 tons, light, (415 tons full load), took place on the 19th of May 1897, and on the 24th of May her official full-power speed trial took place. A mean speed of 30.10 knots was attained on the six runs over the measured mile, and the speed for the three hours' continuous steaming trial was 30.12 knots. The official full-power coal-consumption trial of H.M.S. Griffon took place on the 25th of May 1897, a mean speed of 30.04 knots was attained on the six runs over the measured mile, and the speed for the three hours' continuous steaming was 30.02 knots. Laird Brothers of Birkenhead had built both the Earnest and the Griffon for the British Government.