Almost metric

The Japanese introduced the metric system of measurement back in 1891 as part of the modernization of their nation. Some 80 years later and early in my education the UK went metric. I began school learning the British imperial system of inches, gallons, and miles and finished it immersed in centimetres, litres and kilometres. By the end of my student days I was studying the Japanese language, which was a dogged, albeit enjoyable, task of mastering new words, grammar and the writing system. Fortunately, however, the Japanese effort to go metric all those years ago meant the need to learn the Chinese based, complex measurement system of feudal Japan was long gone. Or, so I thought.

Some eleven years ago I moved to the Japanese countryside of Kunisaki. Unlike the close quarters of my old haunts of London or Tokyo, now open fields and forests surround my home. Along with talk of rice, timber and cows, many a local conversation is peppered with terms like cho, tan, tsubo and, occasionally, se. All these are measures of area but none are metric and I had no idea what a tan, cho, or se represented?

From conversations I sensed that a cho and tan are bigger than a tsubo, but is a cho bigger or smaller than a tan? And where does the se fit in? Recently and somewhat belatedly I have set about remedying this lack of knowledge. With the help of a dictionary and the internet, the easy bit has been understanding their relativity: one cho = 10 tan, one tan = 10 se, and one se = 30 tsubo.

All very well and good but didn't the Japanese go metric 117 years ago? Well yes, almost entirely. When the Japanese introduced the metric system there were some exceptions, including area. They tweaked part of their old system making one cho almost equal to one hectare - 0.99 hectare to be precise. At the same time the Japanese also introduce the aaru, a measure equaling the hectare. But the aaru seems to have little favour where I live and is not common currency amongst the locals.

I can guess approximately what a mile or a kilometre is, or calculate fairly accurately my weight from kilos to stones and pounds, and vice-versa. I can also appreciate what an area of a few ten square metres might look like and, indeed, what a tsubo represents - it is two standard tatami mats in size. (A tatami is 176cm x 85.5cm, which was considered enough space for one person to sleep on).

However, for any large area - whether an acre, hectare, a tan or cho - I have no practical idea of what they might look like in size. Similar to many who were brought up in a town house or city apartment, I had little opportunity or need to comprehend an area more than a few tens of metres, or tsubo, in size and consequently have little conception of larger areas. Not necessarily a problem in urban areas but in the country a matter of importance when chewing the cud with the local farmers. Learning the terms has been a start. Now the hard part as I try to train my eye to appreciate the size of a se, tan and cho, which you will remember is almost hectare. P.S. For those who work with the acre, one cho equals 2.451 acres.

Understanding area is taking on greater importance each year as our Community Project gathers pace. In addition to the property we already care for we are currently negotiating with the owners of many tan of arable fields left fallow for decades and also being asked to take charge of an largely natural forest some six cho in area.