There are four ordinary ways to put a botanical into a room, and they are not equivalent.
You can burn it. You can disperse it cold, through an ultrasonic diffuser. You can warm it on a wax or electric plate. Or you can let hot water carry it, which is what the House does, and which is the least fashionable of the four.
The choice was not made for atmosphere. Each method behaves differently, and the differences matter over a hundred evenings rather than one.
Against combustion
Burning any plant material makes smoke, and smoke is fine particulate matter. That is true of incense, of dhoop, of a cone, of a stick, and it is true whether the material is cheap or extremely good. It is why the House does not burn anything and does not intend to.
This is not a moral position about incense, which is beautiful and belongs to a great deal of Indian life. It is a position about what a person should be inhaling deliberately, at close range, every night, in a closed room in the last hour before sleep.
Against continuous diffusion
An ultrasonic diffuser is a fine machine and solves a different problem. It disperses oil into a room and keeps dispersing it, which is exactly what you want if the aim is for a room to smell a certain way.
It is the wrong instrument for a ritual, for two reasons. The first is that the nose adapts. A single note held flat stops registering after a few minutes, and continuous output makes that worse rather than better. The second is that a device which runs for two hours has no shape. There is no beginning to it and no end, and a practice without an end is not a practice.
A ritual needs a first minute and a last one. A machine that runs all evening gives you neither.
Why water
Hot water does three things at once, and does them in the right order.
It carries. Warmth lifts the volatile fraction of a botanical into the air steadily and then tapers as the water cools, which is a natural decrescendo rather than a flat line. It is why the composition drifts across the ten minutes instead of holding one note.
It requires a vessel. Something has to be filled, carried, set down and, afterwards, emptied and rinsed. Those small physical actions are not overhead. They are the beginning and the end of the practice, and they are what a device removes.
And it finishes. The water cools, the vapour thins, and the ritual is over without anyone deciding it is over. Nothing has to be switched off.
One pod, and one day
A pod takes 350 to 400 ml of water, whichever method you keep. A pod belongs to a day. In a bowl it is used once: the water is boiled fresh and discarded with the pod when the ritual ends. In a portable kettle the pod stays where it is, and the same water may be brought back to the boil for a second or a third sitting across the same day.
What does not happen is the next morning. Warm water that has held plant material and then stood overnight is not something to keep, and it is not something to reheat.
This is the least glamorous instruction the House gives and the one we would least like to see ignored.
The part that is not romantic
Boiling water burns, and a vessel of it at chest height in a dim room is a real hazard rather than a theoretical one. The clinical literature on this is unambiguous: a study of paediatric burn admissions in the British Journal of General Practice in 2016 documented sixteen children treated at a single regional burns centre over five years for injuries from domestic steam inhalation, and it is not an isolated report.
So the House states the rules plainly and repeats them on the box. Sit at a comfortable distance and breathe softly, leaning in only from that distance. Do not put the face directly over the vessel or the kettle. Do not tent a towel over your head, whatever you may have been told elsewhere. Set the vessel on a stable surface, away from the edge. Keep it out of reach of children and animals, and do not leave it unattended.
An adult in a chair, breathing normally, at a distance where the air is pleasant rather than hot, is the entire technique.
What it is not
This is not steam therapy and it is not decongestion. Nidravati Vidhana is an aromatherapy preparation for the inhalation of vapour, and the House makes no claim that it treats, prevents or manages any condition of the airway or of anything else.
What the method offers is narrower. A warm aromatic air, a vessel that has to be attended to, and a practice with an end in it.
Nidravati Vidhana is an aromatherapy preparation for the inhalation of vapour only. It is not a medicine, and no part of it is to be ingested.