The South-Pointing Needle

In the picture most people know, a stone spoon lies in the middle of a smooth, polished bronze plate.

Someone gives its handle a light push. The spoon spins. It slows, wobbles once, and comes to a stop.

Another push. It spins again, slows again, wobbles once more, and stops.

It happens every time. And every time it stops, the handle of the spoon turns toward the same direction.

This is not a spoon for soup. It was carved from lodestone, a dark stone dug out of the earth. The stone pulls iron to itself, and nobody has to tell it to. In that picture, the stone is shaped into a spoon with a round bowl and a long handle. The bowl is ground very smooth, then set in the middle of a bronze plate just as smooth. Only one tiny point of the bowl touches the plate. The lightest touch sets it turning.

The spoon appears in a very old book, the Lunheng, written by Wang Chong in the first century. The book says only this: when the south-pointing spoon is set down, its handle points to the south.

It was not made for going anywhere. The spoon stayed on its bronze plate inside the house. It helped the owner read the lay of the land, choose a direction, and pick a lucky hour for important undertakings. It was something to look at and consult, not something to carry.

Honestly, that spoon is still an open question today. The old lines speak only of a spoon and the south. They do not draw it. The familiar picture of a stone spoon on a bronze plate was rebuilt from those lines much later. A researcher named Wang Zhenduo made that model in the 1940s. So the picture everyone knows is the work of a later age, not a drawing left by anyone who lived under the Han dynasty.

Then more than a thousand years passed, and the idea changed its shape.

It was no longer a heavy spoon lying on a plate. It shrank into a needle.

The man who wrote about the needle was Shen Kuo. He was an official under the Song, the dynasty then ruling China. In old age, after he had withdrawn from public life, he wrote a collection of miscellaneous notes. He was the kind of man who liked to stand and watch others at work, then write down every step in detail. So his book holds all sorts of things, from printing to plants, rivers and mountains. And it has one short entry about the needle.

The method is so simple that anyone who hears it wants to try it at once. Take an iron sewing needle. Rub its point against a lodestone, again and again. That is all. A needle that knew nothing has become a needle that can show the way.

The harder part lay elsewhere: how to hold the needle so that it could turn very lightly. Shen Kuo wrote down four ways, and he tried all four.

Float the needle on the water in a bowl. Balance it on a fingertip. Rest it on the rim of a bowl. Or take a silk thread and fix it to the very middle of the needle with a bit of wax the size of a mustard seed. Then hang the needle where there is no wind.

He liked the last way best. Hung from a silk thread, the needle touches almost nothing, so it turns most smoothly and points most truly.

But the best thing Shen Kuo wrote was not the method.

He added one more sentence, calmly, as if it were a small matter: the needle usually leans a little to the east, and does not point due south.

That sentence sounds light, but it carries weight. A man sits beside a bowl of water and looks at his needle. He sees that it does not line up with the south he knows. He does not throw the needle away. Nor does he round off what he writes to make it neat. He records the lean exactly, even though it makes his needle look like a faulty one.

That small lean was not the needle's fault. It belongs to the earth itself, something people came to understand only much later. In Europe, it would be about 400 years before anyone measured it.

Then the needle left the writing desk and went aboard a boat.

Only a few decades later, a man named Zhu Yu wrote down the stories of people who sailed. His book dates from the early 12th century. He tells how the helmsmen knew the coast by heart, every mountain outline, every rocky point. At night they watched the stars. By day they watched the sun. And when the sky was dark and thick with cloud, they looked at the south-pointing needle.

The whole story fits inside those last few words.

On a night like that, a cargo boat sails far from shore, or a fishing boat comes home late. Not one star is left overhead, and thick cloud stretches from one edge of the water to the other. There is no shore to look at, no mountain shape to remember. On every side there is only black water and the sound of it slapping against the planks of the boat.

Before the needle, nights like that left only two choices. Lie still and wait for dawn. Or grope ahead and hope the guess was right.

Once the needle came, the boat carried one more thing: a bowl of water. On the water floats a small needle, and that needle knows where south is. Knowing south means knowing north. Knowing north and south means knowing the way home.

The two words chỉ nam mean pointing south. Vietnamese people borrowed these two words long ago, and they borrowed them in a way all their own.

Kim chỉ nam is the Vietnamese name for the south-pointing needle. Yet today the phrase hardly speaks of a needle anymore. It speaks of whatever guides a person: advice handed down by grandparents, or a principle someone chooses to live by. And chỉ nam on its own became a name given to books that guide the reader. One of the oldest surviving Vietnamese dictionaries is called Chỉ Nam Ngọc Âm Giải Nghĩa. It explains Chinese characters in Nôm, an old character script for writing Vietnamese. Most of it is written in lục bát, a traditional Vietnamese verse form in which lines of six and eight syllables alternate. So it has rhyme and rhythm when read aloud.

The stone spoon stayed behind on its bronze plate. The needle traveled everywhere, because the need for it belonged to no single people. Fishermen and cargo boatmen in every land were the same. Anyone who went far from shore had to know the way home.

A bowl of water, and on it a needle just rubbed against a lodestone. Stand very still and watch.

The needle turns. It slows, wobbles once, and comes to rest.

And at sea, nearly a thousand years ago, at just the moment a needle came to rest like this, the bow of a boat would begin to turn and follow it.