"[B]y the end of 1943 Nervi's firm was at work on three 150-ton transport boats, their hulls completely of ferrocement, and one 400-ton vessel, largely of ferrocement. The first construction was interrupted by the war, and it was not until 1945 that Nervi's method resulted in... [t]he Irene... a motor boat with a 165-ton displacement. On a supporting frame of 1/4" steel rods spaced about 4" apart, Nervi spread eight layers of wire mesh, four on each side of the rods, which were tied tightly together and plastered by hand with a rich cement mortar. The resultant ferrocement was 1 3/8" thick (about the same thickness as Lambot's boat). Other than the rods sandwiched into the mesh, no formwork was needed."