Bonshō

About Bonshō in brief

Bonshō are large bells found in Buddhist temples throughout Japan. They are struck from the outside, using either a handheld mallet or a beam suspended on ropes. 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 earliest of these bells in Japan date to around 600 CE, although the general design is of much earlier Chinese origin. The bells’ penetrating and pervasive tone carries over considerable distances, which led to their use as signals, timekeepers and alarms. They play an important role in Buddhist ceremonies, particularly the New Year and Bon festivals. In modern times, bonshē have become symbols of world peace. Bonshô are cast in a single piece using two moulds, a core and a shell, in a process that is largely unchanged since the Nara period. The core is constructed from a dome of stacked bricks made from hardened sand, whilst the shell is made using a strickle board. After the metal has cooled and solidified, the mould is removed by breaking it, therefore a new one has to be created for each bell. Only around 50 per cent of castings are successful on the first attempt, without cracks or imperfections.

The casting is traditionally accompanied by the chanting of Buddhist sutras, which may go on for several hours. The ratio of the alloy is usually around 17: 3 copper to tin; the exact admixture can alter the tone of the end product. Some bells retain linear impressions arising from joints in the mould used; they are not removed during fettling but are regarded as an aspect of the Bell’s overall beauty. The bell’s appearance and sound are intended to be in keeping with Japan’s wabi-sabi aesthetic. A well-made bell should produce a clean, clear tone. There are also continuous harmonic overtones that can be also be heard up to 32 kilometres away on a clear day. The difference of a single bell is judged by its creators, and a difference of single frequency can require the bell to be judged by the creators. The initial sound is immediately followed by the prolonged oshi, which is higher in pitch and is rich in low sorrowful airics; it lasts up to ten seconds. Finally comes the belluri or decay, the vibration that is heard as the bell dies away, which can last up to a minute. This is the sound of a rumble with a rich, rich, harmonious sound that continues for a long time.