Measuring Time by an Incense Stick Instead of a Timer

There was a shelf in my grandmother's kitchen, above the flour tin, that held a matchbox, a bundle of agarbatti tied with pink thread, and a small square of folded cloth she used for nothing else. The house had a clock. It was in the other room, it was slow, and nobody wound it.

What she used instead, most mornings, was a stick.

She would light one, wedge it into the crack at the back of the shelf where the plaster had gone soft, and say the sentence I must have heard a few thousand times: jab tak agarbatti khatam na ho. Until the stick finishes. Grind until the stick finishes. Sit until the stick finishes. Then you may go and ask me about it again.

At eight I thought this was an unfair and probably invented unit of time. I am now a person who uses it three or four mornings a week.

The unit was a length, not a number

It took me an embarrassingly long while to notice the actual cleverness of it, which is this: the stick was not measuring minutes. It was measuring a length.

A clock gives you a number and the number is always in relation to something else — how late you are, how much is left, how long this has already taken. A burning stick gives you a diminishing object. You look up, you see three fingers of it left, and you have learned everything you needed to know without arithmetic. Nobody in that kitchen ever asked how many minutes an agarbatti was. The question would have made no sense. The stick was the unit.

And because it was a length, it was honest about being approximate. A thicker stick lasted longer. A stick from a damp packet in the monsoon behaved differently from one out of a dry tin. Under the window on a windy afternoon it went quickly and everyone knew it went quickly. The unit flexed with the weather, and nobody minded, because nothing in that kitchen was being timed to the second.

Where the real instruments were

I would love to tell you that my grandmother's shelf was the last surviving branch of an ancient Indian science of measuring time by smoke. It was not, and I should say so plainly.

The instruments genuinely existed, but the record for them is Chinese and then Japanese. Incense clocks appear to have been in use in China by around the sixth century, and the elaborate metal versions belong to the Song dynasty period. The most beautiful of them is the incense seal: a shallow tray filled with a smoothed bed of ash, into which a stencil presses a continuous maze-like groove of powdered incense. You light one end of the path and it burns its way along, hour after hour, so that the time is written across the tray as a line of ash advancing behind the ember.

Some were made to be read without looking. Different scents were laid along different stretches of the path, so a change in the room told you the hour had turned. Others carried threads with small weights across the burning line — when the ember reached the thread, the thread parted and the weight dropped onto a metal tray with a chime. Chinese physicians are described notching sticks so a patient would know from the burn line when the next dose was due.

In Japan the practice went commercial. A geisha's time was billed by the number of senkō-dokei — incense clocks — consumed while she was present, a way of charging that continued until 1924; one stick ran roughly half an hour, and an evening with a single guest often came to about four of them. By some accounts the burnt stubs were kept aside as the night's receipt.

As for India: as far as I can find, no incense clock has been found here. The historian Edward Schafer noticed Devanagari carvings on early Chinese seals and wondered about an Indian derivation; Silvio Bedini argued that the script travelled with Tantric Buddhist texts translated into Chinese and that the timekeeping function was a Chinese addition. That argument is not settled and I am not qualified to settle it.

So my grandmother did not inherit an instrument. She had a habit, which is a different and in some ways sturdier thing.

It was never precise, and that is the feature

If you go looking for how long "one stick of incense" is supposed to be, the sources will not agree with each other. You will be told five minutes. You will be told fifteen to thirty. You will be told forty-five, and you will be told half of a two-hour shichen, which is an hour. All of these are offered with equal confidence.

They cannot all be right, and the reason they conflict is the whole point: it was a figure of speech before it was a measurement. It meant a while, of the sort you can see the end of.

Our own sticks are no different. We make them in Samastipur and roll them by hand, and I still cannot give you an exact number for one — a full-length stick from a dry packet in still air will usually run somewhere in the region of half an hour to forty-five minutes, and I would not want to be held to that in a draught. If you want a precise instrument, buy a precise instrument. What you have here is a length.

What a burning stick does that a phone cannot

I am not going to tell you that incense makes you calmer. That claim gets made too easily and I have no way to prove it to you about your own morning.

What I will say is narrower, and it is about the timer, not the smoke.

It has no alarm. It ends by absence. You realise a minute or two afterwards that the room has stopped smelling, and by then you have already finished, without being cut off mid-thought by a sound designed to be impossible to ignore.

It is readable without being a number. You glance, you see what is left, you go back. No figure arrives to tell you that you are behind.

You cannot pause it. This turns out to carry most of the moral weight. A phone timer can be extended, snoozed, restarted. A stick that has burned two-thirds down is two-thirds down.

It is not on your phone. For a lot of people, the surest way to lose a quiet twenty minutes is to pick up the phone in order to start timing them.

One honest caveat: if smoke is difficult in your house — a small room, a sensitive chest, a neighbour's shared balcony — do not force this. A sand timer does the same job silently, and the point was never the smoke.

If you want to try it

• Calibrate once, then stop. Light one stick from the box you actually use, note the time it starts and the time it finishes, once. After that, don't look. The number was only ever to reassure you that the length is a sane length.
• Keep to one box. Your unit is that box. Switch brand or thickness and you have quietly changed your unit.
• Still air. Away from the fan, the window and the air-conditioning vent. A draught can take a third off it and you will feel oddly cheated.
• Half a stick for a shorter sit. Snap it before lighting rather than relighting a charred one — a relit black tip is mostly ash, and it smells like it.
• Don't use it for anything that needs precision. Not the pressure cooker. Not a call. Use it for a sit, a stretch, one piece of uninterrupted work, a child's homework block, the half hour before the house wakes up.

My grandmother was not teaching me about attention. She wanted the grinding done and she wanted me out of her kitchen. But the instruction was better than she knew, because it handed me a quantity of time in the form of an object that was visibly spending itself in front of me whether or not I did anything useful with it.

I have never found an app that does that.