My morning walk in the leafy, wide boulevard near my house is always filled with the sound of birdsong. But generally this is ruined by the cacophony of men clearing their throats before spitting on the pavement.
So, instead of admiring the laburnum trees laden with glorious yellow flowers, I am forced to walk with my eyes glued to the ground, in order to avoid a messy encounter.
It's not just poor Indians who perform this disgusting morning ritual. The rich are just as much to blame as the caretakers, guards and gardeners - starting their work in the homes of the rich - or the labourers I see walking from their slums past the mansions to the building sites where they will earn US$1 a day.
The other day, startled by a violent noise behind me that scared the birds out of the trees, I turned round, hoping that my severe look would shame the labourer responsible. In fact, it turned out to be an elderly, dapper gentleman getting into his car. But such dirty habits don't end there: energetic nose-picking, groin-scratching and urinating in the street are all inescapable features of Indian public life.
These are all gross habits, and they betray a total lack of consideration for others.
However, there is one thing that really makes me shudder, even after a decade of living in New Delhi: men blowing their noses into their hands, then wiping them on their trousers or against a wall. Others, it has to be said, do pull a clean handkerchief from their pockets afterwards, and wipe their hands on that. Which begs the obvious question ...
I couldn't fathom the perverted logic behind this until I read Jean Baptiste Tavernier, a Frenchman who travelled through India in the 17th century and was one of the first western observers of Indian society. In Travels in India, Tavernier observed that Indians were revolted by westerners' habit of blowing their noses in a handkerchief then keeping it in their pocket all day. They prefer, he notes, to get rid of the offending substance in the road, on the principle that it's better 'out' than 'in'.
This all has deep roots. It is a key concept in ayurveda, or traditional Indian medicine, that eliminating all waste from the body is essential. Hence the noisy ablutions performed in bathrooms (or on the streets) every morning - and the obsession with regular bowel movements.
Internal cleansing routines are considered an important route to good health, as they restore the body's natural balance. That explains why ayurveda shops stock 'nasal cleaning pots'.
I have no objection to internal cleansing. It sounds sensible enough. I just wish that Indian men would perform it internally, too - in the bathroom, with the door shut.