Among the most impressive examples of early bronze casting in Japan are large, bronze bells known as do_taku. Metallurgy, together with wet-rice cultivation, was probably first introduced to Japan by a new wave of immigrants from the Korean peninsula during the 3rd century a.d. Although do_taku resemble Chinese bells in overall shape, most lack musical resonance because of the thinness of their casting. Thus, do_taku seem to have been ritual objects and symbols of political authority. This bell was one of fourteen excavated in 1881 on Mt. O_iwa in Shiga Prefecture.