Of all the examples of human misery on such open display in this remarkable, terrifying, contradictory city, few are more moving than the hand-pulled rickshaws. For a handful of coins, an often-barefooted man dressed in little more than a dhoti tied around his waist will pull his passengers through the noisy, cluttered streets. Life as a rickshaw-puller is hard, difficult and usually short. Many of the 20,000 pullers are migrants from Bihar and many sleep on the streets. They are lucky to make more than $2 (£1.30) a day. "I only have the clothes I am wearing right now. I am very low," one puller, plying his trade at a temple in the south of the city, tells me. He is painfully thin: his leg is barely the size of someone's arm.
Actually there should be no rickshaw pullers here. Following a campaign by activists who said such labour had no place in civilised society, the authorities last year amended legislation to ban them. The trouble is that they failed to provide alternative employment for these men, so they resisted the ban and for now the pullers remain. So, should I ride in a rickshaw? My instincts are utterly against it. But outside a metro stop, some pullers are lined up and they hail me. I clamber on, persuaded that while they exist, any contribution I can make in the shape of a decent tip might help them, if only for a day.
We set off through the chaotic back streets. We pass a group of tourists and I make sure not to catch their eye, suddenly embarrassed. When we stop I pay the puller the equivalent of a good day's earnings. In truth, it is a tiny sum but he looks very happy. I still feel bad.
The draw of ancient beauty
The Asiatic Society on Park Street is a historical treasure trove and perhaps houses the most important collection of South Asian manuscripts. I have only ten minutes to spare, but the museum's wonderful curator, Keka Banerjee, gives me a guided tour, pointing out manuscripts in languages as diverse as Sanskrit, Assamese, Pali and, of course, Bengali. The most precious, she tells me, is the Kubjika Mata, a 7th Century text of tantric virgin worship. The manuscripts are amazing and beautiful. In a city where beggars lurk on every corner, I am again reminded of India's incredible richness and complexity.
Trams: shake, rattle and extol
A ride on an ancient tram costs just four rupees (about six pence). We're not sure where it's heading but in the spirit of adventure we leap on and rattle through the city. Apparently these too are being phased out, but unlike the rickshaw experience, we feel exhilarated by this bumpy ride.