[2] They were powered by a three-cylinder vertical triple-expansion steam engine developing 1,400 horsepower (1,000 kW) and driving a single screw.

[2] The class was originally designed and built with barque-rigged sails, but both ships were re-rigged as barquentines before 1900 by removing the main yards.

[1] Screw sloops of Alert's type had been obsolete for many years, but they remained ideal for patrolling Britain's far flung maritime empire.

Alert served on the North America and West Indies Station, including a period in late 1902 and early 1903 when, under Commodore Montgomerie in HMS Charybdis, she enforced a blockade of the Venezuelan coast.

She was laid up for a time at Bermuda, but after 1910 served on the East Indies Station in the Persian Gulf, employed in the suppression of gun-running.