- 3 * cylindrical boilers
- 2-cylinder horizontal compound-expansion steam engine
- Single screw
- 2 * 7-inch (90cwt) muzzle-loading rifles
- 4 * 64-pounder muzzle-loading rifles
- 4 * machine guns
- 1 * light gun
The Doterel class was a Royal Navy class of screw-driven sloops. They were of composite construction, with wooden hulls over an iron frame. They were a revised version of an 1874 design by the Royal Navy's Chief Constructor, William Henry White, the Osprey-class sloop. Two of the class were lost, one to an explosion off Chile and one wrecked off Canada. Gannet is preserved at Chatham Historic Dockyard.
The Nathaniel Barnaby design was a development of William Henry White's 1874 Osprey-class sloop. The graceful clipper bow of the Opsreys was replaced by a vertical stem and the engines were more powerful. They were of composite construction, with wooden hulls over an iron frame.
Power was provided by three cylindrical boilers, which supplied steam at 60 pounds per square inch (410 kPa) to a two-cylinder horizontal compound-expansion steam engine driving a single 13-foot-1-inch (3.99 m) screw. This arrangement produced 900 to 1,128 indicated horsepower (671 to 841 kW) and a top speed of between 11 and 11.6 knots (20.4 and 21.5 km/h).
They were armed with two 7-inch (90cwt) muzzle-loading rifled guns on pivoting mounts, and four 64-pounder muzzle-loading rifled guns (two on pivoting mounts, and two broadside). Four machine guns and one light gun completed the weaponry.
All the ships of the class were provided with a barque rig, that is, square-rigged foremast and mainmast, and fore-and aft sails only on the mizzen mast.