One of the world's man-made wonders - which for nearly 350 years has survived wars, earthquakes and a mad scheme to sell off slabs of it for English garden follies - has now fallen prey to acid rain. Pollution from 1,500 factories and an oil refinery has given the Taj Mahal what scientists call 'marble cancer'.
Once as white and ethereal as a cloud, the Taj Mahal is now stained yellow like a cigarette smoker's teeth. The pearl-white marble, quarried from Rajasthan, is now blotched, dull and flaking. The exquisite intaglio inlay, crafted by goldsmiths and jewellers, is corroded and gouged-out by souvenir-hunters.
Enter Mr Mehta, a grey-bearded man who bristles with energy. His law office is cramped with books, and his pet Dachshund moves about the carpet like a Hoover. On his desk sits a cheap little replica of the Taj Mahal, the kind that sell for a few rupees in tourist shops all over India.
Every Friday for the last 10 years, Mr Mehta has donned his advocate's robes and starched white collar and gone off to do battle at the Supreme Court on behalf of the Taj Mahal. He is trying to convince the Supreme Court to either move or shut down the many iron foundries, glass and car- parts factories and a petroleum refinery which ring the Moghul tomb in sulphurous smoke.
He is an eloquent speaker, but when asked to describe the Taj Mahal, Mr Mehta begins to reply: 'It's like I am dreaming this monument. It's so beautiful it's almost not real . . . I can't explain its beauty.' Frustrated, he gave up and produced a photocopied sheet of quotes from famous visitors to the Taj Mahal, such as King Edward, Edward Lear and Eleanor Roosevelt. Apparently, the lovelorn Princess Diana made no memorable utterances when she viewed the Taj Mahal alone before her break-up with Prince Charles.
The most succinct remark in Mr Mehta's collection comes from Shah Jehan, the emperor who ordered the mausoleum to be built for his favourite wife, Mumtaz Mahal, who died in 1631 delivering her 14th child: 'The builder could not have been of this earth, for it is evident that the design was given to him by heaven.' Mumtaz, rare for those days, would accompany her husband on military campaigns and advise him on tricky state affairs. Shah Jahan grieved for two full years after his wife's death, wearing drab clothes and forsaking music.
Not only was Shah Jahan a romantic, he was also an able architect who interested himself in every detail of the 22-year building project, which required more than 20,000 workers. It is said that the emperor was so pleased with the masterpiece that he had the chief mason's hand chopped off so he could never duplicate it.
To appreciate the enormity of Mr Mehta's task in trying to save the Taj Mahal - and his tenacity - it is worth mentioning that India's Supreme Court is swamped with more than 150,000 pending cases. Still, Mr Mehta, with help from P N Bhagwati, a former chief justice, managed to persuade the slow-moving Supreme Court in 1991 to close down 212 factories in Agra, where the Taj Mahal is located, and in nearby Firozabad. At his prodding, the Supreme Court also ordered the Environment Ministry to plant 36,000 trees, making a green belt around the Taj Mahal.
'India has fine environmental laws, but on paper only,' Mr Mehta said. 'The government has no priority in saving the Taj Mahal. Some factories have closed down but many more have opened up, illegally.' He is circulating a petition world-wide, trying to obtain a million signatures, which he hopes will shame the Indian government into closing down the industries menacing the monument.
Mr Mehta and many Indian ecologists are pushing for the creation of a 'trapezium', an area covering more than 6,000 square miles in which all heavy, polluting industry would be banned. This environmental swathe would stretch from Agra all the way to Rajasthan, encompassing Mathura and Vrindavan, two holy Hindu sites, and the Bharatpur bird sanctuary.
Opponents claim the shutting down of brick kilns, iron foundries and the Mathura petroleum refinery would leave over 100,000 workers unemployed. Mr Mehta replies that the central and state governments should relocate the industries elsewhere if they want to save the Taj Mahal. 'If stone can get cancer, imagine how susceptible humans are to the pollution,' he said. Emissions of sulphur dioxide around the Taj Mahal are twice the permissible levels. The refinery dumps 1,000 kilos of noxious sulphur dioxide into the air every hour.
Warnings were sounded as far back as 1984, when a joint study carried out by Indian and American scientists concluded that 'a yellow pallor pervades the entire monument. At places the yellow hue is magnified by ugly black and brown spots.' The worst damage is inside the crypt, where the tombs of Shah Jehan and Mumtaz Mahal lie side-by-side encrusted with semi-precious stones. Many of the Taj Mahal's 25,000 daily tourists rub their grimy hands over the inlaid flowers inside the tomb, speeding the growth of a fungus which blackens the marble.
The cash-poor Archaeological Survey of India only has a annual budget of pounds 20.5m for the upkeep and repair of over 3,000 monuments across India. Of that, only pounds 41,000 is spent on the Taj Mahal, India's best known monument. 'They have unskilled labourers trying to scrub the marble clean with a toothbrush,' snorted Mr Mehta. 'It's just not enough.'