How People Measure Things

To measure a thing is to ask a question that ends in a number: how long? how heavy? how far? People need this at all times — to make buildings that do not fall, to buy things and pay the right amount, to make a part in one country that will go into a machine in another.

The first measures

The first measuring things were bodies. A length was a number of feet — a man's foot, put down one after another — or a number of hands. But feet are not all the same: a big man's ground was bigger than a small man's ground, and people were often angry at each other about it.

The measures made from the ground

About two hundred years before now, in the country known for its good bread, in the angry years, people decided to make measures that were the same for all people, taken from a thing all people have: the ground. Take the distance from the cold top of the round stone we live on down to its hottest line, and cut it into ten thousand thousand parts: one part is a meter. Make a container as wide as your hand on each side, and put water in it: the weight of that water is one kilogram.

All of it goes by tens: ten of one thing makes the bigger thing, and ten of that makes the one after. Zero, one, two, three, four, five, six, seven, eight, nine — and then you start another ten, and count on your hands.

Why it is not a small thing

Not all countries changed. One big country holds to the foot to this day. One time, two groups made telling words for a flying machine that was going to another ground. One group measured with meters; the other measured with the measures from before; no one compared them. The machine went all that far — and then, at its end, it was gone.

A meter in one country is a meter in all countries now. It is one of the things that all countries say yes to, and there are not many of these.