Bonshō, also known as tsurigane or ōgane are large bells found in Buddhist temples throughout Japan, used to summon the monks to prayer and to demarcate periods of time. Rather than containing a clapper, bonshō are struck from the outside, using either a handheld mallet or a beam suspended on ropes.
The bells are usually made from bronze, using a form of expendable mould casting. They are typically augmented and ornamented with a variety of bosses, raised bands and inscriptions. The earliest of these bells in Japan date to around 600 CE, although the general design is of much earlier Chinese origin and shares some of the features seen in ancient Chinese bells. The bells' penetrating and pervasive tone carries over considerable distances, which led to their use as signals, timekeepers and alarms. In addition, the sound of the bell is thought to have supernatural properties; it is believed, for example, that it can be heard in the underworld. The spiritual significance of bonshō means that they play an important role in Buddhist ceremonies, particularly the New Year and Bon festivals. Throughout Japanese history a number of these bells have become associated with stories and legends, both fictional, such as the Benkei Bell of Mii-dera, and historical, such as the bell of Hōkō-ji. In modern times, bonshō have become symbols of world peace.