The son of an impoverished family of naval tradition, Peral got a special scholarship from Queen Isabella II in order to build a career, and he soon proved to be an Omnidisciplinary Scientist on the making. After a career as a Plucky Middie that saw him traveling around the world, he participated in the Ten Years' War in Cuba, as well as the Third Carlist War, earning a fair lot of medals before a grave illness forced him into a job as a teacher in the navy's academy in Cádiz.
For Peral, however, this was a chance to develop a project that occured to him during the 1885 Carolines Crisis between Spain and Germany. The idea of an attack submarine vehicle had been already tested by some people, more famously the American undersea bike Turtle and the more famous Confederate man-powered ship Hunley, as well as a Chilean cannonier projected by Karl Flach, but Peral wanted something much more complete and solid: a submarine ship moved totally by electricity and which could fire torpedoes while submerged, like a torpedoboat did on the surface. Although it's unknown whether Peral was aware of it, his model would be as advanced for his time as the designs conceived by fellow Spaniard Jerónimo de Ayanz would have been back in the 16th century had them ever left the drawing board.
Contrary to popular belief, even in Spain, Peral wasn't the first to build a submarine, as Narciso Monturiol beat him at this in 1859 by deploying the the first air-independent and combustion-powered submarine (which Monturiol even tried to sell to the United States to counter the Hunley), one year after which Cosme García Sáez cobbled together a ship similar to that of Flach (which was eyed by Napoléon Bonaparte's nephew the Third). However, Peral combined the attributes of all models seen up to the point and improved them with his own ideas, and with the blessing of Queen Maria Christina, he launched his magnum opus, the Peral, in September 8, 1888. In front of the eyes of the Spanish admirals, the submarine performed excellently in all the tests it was subjected to for two years, only failing at one test out of several,note with generally favorable results that even granted Peral a medal. Pundits would later say that the Peral's capabilities weren't matched by foreign models until more than a decade later.
Despite this success, when Isaac asked for support to develop further his model, the Spanish Navy unexpectedly told him to get lost. A lot of books have been written about what exactly happened, but the quick version is that Peral's project was taken down by shady political interests headed the infamous Greek arms dealer Basil Zaharoff, who had tried to buy the submarine for his English and American clients and enlisted the help of Spanish Freemason politicians to take it down when Peral refused. Eventually, a frustrated Isaac burned all of his plans to avoid foreign spies copying it, and the Spanish submarine project died right there, not much before Peral himself, harassed and disgraced.
When the 1898 Spanish-American War came stomping around, the Spanish Armada was defeated for good, this time not by a untimely storm, and it left the perception in modern Spain that, had Peral been given the opportunity to produce a flotilla of Perals and deploy them in Cuba and Manila, the course of the war would have been starkly different, an opinion also attributed to American Admiral George Dewey, the victor of Manila himself.note Another Spanish inventor by the name of Antonio Sanjurjo, interestingly a personal friend of Jules Verne, did deploy during the war a sort of submarine minelayer in case continental Spain was attacked, but as this never happened, his work was equally forgotten.
Peral's work was reappreciated over the years (in true Spanish fashion, when it was way too late), and nowadays a lot of Spanish streets, and four submarines of the New Spanish Armada, carry his name.
- Fermín mentions him in Carlos Ruiz Zafón's The Labyrinth of Spirits, although amusingly conflating him with Monturiol.
- Cuarto Milenio ran a reportage on him in 2017, featuring the presence of Peral's grandson Javier Sanmateo Isaac Peral.