A submarine for Portugal according to the Dutch magazine Marineblad dated 1910-1911 no. 7

An item reported that an Italian shipyard was building a submarine for the Portuguese navy. Her dimensions were to be 45,15 x 4,20 metres with a displacement of 245 (surfaced)-300 (submerged) ton and further more a speed of 8 (submerged)-13 (surfaced) miles. She was to be fitted out with two periscopes.