The lives of these women, portrayed in a play that opened last week in Bristol called Women of the Dust, are poor and unsettled. They are migrant workers from rural backgrounds, who move on to the next project when their work is done and never belong to the cities they build.
Every stone block that went towards fulfilling Sir Edwin Lutyens's monumental vision of New Delhi, capital from 1911 of Britain's Indian empire, was hefted into place by female labourers. Khushwant Singh, a Sikh writer and historian whose father was one of the Raj's biggest contractors in Delhi, remembers: 'While our clerks and accountants quarrelled over how much profit they had made that day, the female workers would all go back to their tents at dusk singing lustily. I think they were paid six annas a week. It was an insignificant amount.'
Wages for a female construction worker are still insignificant. For a 10-hour shift she collects 28.60 rupees (around 50p), which the foreman pays directly to her husband.
One day in 1967, Meera Mahadevan, a Delhi socialite, saw a lorry run over a child who had strayed from his mother, who was laden down with bricks. The socialite had one of her servants take up position under a tree on the construction site to serve milk and roti bread to the children. From that beginning an organisation called Mobile Creche was created which now runs 400 daycare centres in Delhi, Bombay and Pune.
The work done by the Mobile Creche attracted the interest of Oxfam, which last year commissioned a British-based theatre company, Tamasha, to write and perform Women of the Dust. The play's author, Ruth Carter, visited India with the actress Sudha Bhuchar, who has recently featured in the radio soap The Archers, and the theatre director Kristine Landon-Smith. 'We made a strange sight: two white girls and a brown girl wandering around these dusty construction sites in Delhi,' Ms Carter says.
In Women of the Dust, Ms Bhuchar plays a labourer from Rajasthan, forced by a drought to leave her village. Other characters include a labourer's husband who, after failing to improve his family's chances of survival after two years of ceaseless toil, turns to drink; a 10-year-old child bride; a foreman who recruits the families from the impoverished villages and extracts his tithe; a wealthy contractor who represents the new, affluent Indian middle class; and two Oxbridge-educated sisters, one bubbly and the other introverted, who are staging a charity ball, with the Princess of Wales in attendance, to raise funds for a rural development programme. They have women in the villages sewing tiny beads on evening bags sold in the best London boutiques.
The play is lyrical and personal, yet it deals with the broader problem of charity's double edge: people want their lives to be improved with their traditions intact, not messed about by patronising do-gooders under the banner of 'development'. In the play, two female labourers joke about a project in which a social worker from Bombay tried to get them to use a newly designed stove. 'We sat on the ground listening politely to this woman in a silk sari, her hair oiled and her cheeks plump. We sat on the ground, our lips cracked, our babies sucking air. She demonstrated a vegetable daal. We had no vegetables, but we came every day. We were very attentive. She was so beautiful. Like a goddess. Her voice was soft. Her eyes were so shining. We had nothing to cook on these stoves. But we came every day to look at her face and listen to her musical voice. She was like a goddess. Now in Delhi we have the cinema.'
A drama commissioned by a charity organisation runs the risk of lapsing into propaganda, but as Ms Carter explains: 'I didn't find any evil characters when I was doing the research - even the contractor and the foreman have their pressures. As for the women, I wanted to show them as they are: they're not people from Mars. They're not any more overtly heroic than anyone else. They're like us.' She hopes a British audience 'will leave the theatre thinking: look, I may be hard up but I can still spare a quid for charity.'
Brinda Singh, chairwoman of Mobile Creche, says: 'It's hard to tell how much good we've done. These women and their children are like nomads. But I think we've probably touched the lives of over 200,000 children.'
One of the 190 Mobile Creche centres in Delhi is on the university campus, where families of labourers from the states of Rajasthan, Madhya Pradesh and Bihar are putting up modern housing blocks for the faculty of the National Institute of Immunology. The workers live in a warren of mud huts behind a building where monkeys are kept for scientific experiments, and on days when food is brought for the monkeys, the children gather around the lorry, hungrily watching this feast of bananas and papayas being carried inside.
Inside the creche, decorated with strings of coloured paper and simple drawings, there are women rocking cradles, while in the next room older children prepare for an excursion to a bread factory. Their mothers have made them wear their best Western clothes and slicked down their children's shiny black hair.
One 12-year-old boy is inconsolable. The night before his older sister had fled the family hut after being beaten by her father. The boy went searching for her in the wilderness of thorn bushes behind the university campus and stumbled upon a gang of men burning a corpse. He ran home, breathless, through the thorns. 'Everywhere he is seeing ghosts,' says Sunisha Ahuja, one of the creche workers, as she comforts the gaunt-faced boy.
The women pay half a rupee a month for the creche. It is not enough to meet costs, but it gives the labourers a sense of participation in their children's upkeep.
Ms Carter's visit to India had included a trip to Rajasthan, a desert region in north-west India bordering Pakistan, which gave her an understanding of the strong magnetism that rural life, with its traditions and Hindu customs, still exerts on the families of migrant labourers. One of the characters in the play, Asha, yearns to leave Delhi and deliver her first baby in her home village, but her drunken husband squanders the money for their coach ticket on a broken television set.
When I recounted the play's plot to the women at the creche by the monkey house in Delhi, they seemed to find it plausible, especially Asha's desire to give birth back in her village home, whitewashed and smelling of sweet herbs. Arriving in Delhi from Rajasthan can be a trauma for first-time labourers. They are terrorised by the noise, the traffic, the multitude of strangers who treat these migrants with contempt.
These graceful women may have built New Delhi, with its broad, green boulevards, its domed government offices and marble-clad hotels. But they do not belong in the cityscape they have created. They are expected to become invisible, women vanished in the dust.
'Women of the Dust' is at the Bristol Old Vic (0272 250250) to 31 October; Riverside Studios, London (081 748 3354), 4-28 November; Phoenix Arts Theatre, Leicester (0533 554854), 4-6 December; the Arts Centre, Warwick University (0203 524524), 11-12 December.