Her hull shape, propeller, periscope, torpedo launcher and cruciform external controls anticipated later designs.

[citation needed] Although advanced in many ways, Peral lacked a means of charging batteries while underway, such as an internal combustion engine, thus had a very limited endurance and range.

[8] After several studies and experiments, and having gained support from his superiors and fellow officers, Peral exposed his idea to the Spanish navy staff.

After the interview Pezuela agreed to finance Peral's preliminary studies in Cádiz with an initial budget of 5,000 pesetas, before launching a program to build a full-scale submarine.

[citation needed] On 21 July 1886, the new Navy Minister, rear-admiral Beranger, decided that the project would be reviewed by the Centro Técnico de la Armada (Naval Technical Center), under the responsibility of Admiral Antequera.

On 17 March, the Commander in Chief of Cadiz, Florencio Montojo, who headed the technical committee overseeing the machine, requested budgeting for Peral's submarine.

On 25 April 1887, the submarine's construction was finally approved by the government; the keel was laid down on La Carraca on 7 October, although work did not start until two weeks later.

He also devised a periscope, a fixed tube on the turret; by using a series of prisms, it projected the outside world to within the submarine.

[citation needed] The range of the boat again depended on battery charge level; Peral calculated his original submarine could reach 132 nmi (152 mi; 244 km) at a speed of 6 kn (11 km/h; 6.9 mph).

[citation needed] One of the original features of Peral was an underwater lamp, which enabled the crew to search the sea bottom.

[12] The submarine was single-hulled, and the ballast tanks were located at the bottom of the hull, underneath the torpedo tube.

[citation needed] Peral was launched on 8 September 1888, sixteen days before another pioneering electric submarine, the French Gymnote.

On 25 June 1890 Peral made two simulated attacks on the cruiser Cristóbal Colón, one during daylight and other at night.

The speed and endurance of the Peral attained World War I standards (in terms of underwater, battery-powered sailing).