A development of the Amazon class, they were designed by Edward Reed, the Royal Navy's Director of Naval Construction.

The hull was of wooden construction, but with iron cross-beams, and a ram bow was fitted.

[1] Propulsion was provided by a two-cylinder horizontal steam engine driving a single screw.

The Eclipse class was designed with two 7-inch (6½-ton) muzzle-loading rifled guns mounted in traversing slides and four 64-pounder muzzle-loading rifled guns.

[1] They were re-classified as corvettes in 1876, carrying a homogenous armament of twelve 64-pounder muzzle-loading rifled guns.