Roy Moxham, pub: Constable, London. 2001, 256pp, hb £14.99. ISBN 184-119-2600

It may be just as well that Roy Moxham and his publisher got this book out in January. If they had left it a couple of months, there would have been some danger that many potential readers could have dismissed it as an elaborate April Fool trick, so far has this episode of history slipped from our consciousness.

In fact, it is compelling tale of historical detective work and dogged determination, the story of one man's search for any remaining vestiges of a barrier against smugglers of salt and other commodities into British India. The hedge did exist. By poring over masses of documents and old maps, Moxham established that beyond doubt, and he set himself the task of finding any of it that had not gone under the plough or been buried under new roads. For hundreds of miles, until it was abandoned in 1879, it formed a huge part of the customs line that eventually ran from North of Rawalpindi, in what is now Pakistan, to Orissa, bordering the Indian Ocean. It was compared by A O Hume, one of its principal builders, later Secretary to the Government of India, to the Great Wall of China as the "greatest work and chiefest safeguard" of British India.

Roy Moxham's knowledge of, and affection for, present-day India and its people are very apparent in his accounts of visits to areas of the country well away from the usual tourist routes, and in his exposure of the extent of the plunder wrought by colonial rulers. The extent of the greed of the East India Company and its chief officer in India, Robert Clive, is shocking even to a readership conditioned by awareness of British doings in other parts of the globe. Clive became immensely wealthy, effectively defrauded the company through which he had gained that position, and protected himself from redress through parliamentary action by buying up rotten boroughs.

"British individuals, and most of all the East India Company itself, took vast sums out of India and spent it in Britain. India, which when the British arrived had been relatively well-off, became much poorer." Through land revenues, a salt tax that cost poorer families up to one-sixth of their annual income, and actions such as cornering the market in rice, the Company and its agents looted the country. When crop failures occurred, the subsequent increase in the price of grain by up to twenty-fold simply increased their profits. During the 1770 disaster, the generosity of the Company extended to 90,000 rupees to relieve the suffering of some 30 million people.

When it came, control by the British Government through the Governor-General, and later the Viceroy, was exceedingly slow to alleviate the situation and although much reduced, the Salt Tax remained a central and symbolic complaint when Ghandi began his protests in the 20th century.

Although some of his chapters, such as the survey of effects of salt deprivation around the world, read rather dryly and give the air of having been introduced at the behest of an editor looking to increase the bulk of the book, this remains a compelling read. By putting the hedge, its builders, its purpose and its effects under his magnifying glass, Moxham gives us a sharper view of a large and important chunk of our history. His book deserves a wide readership, one that I hope will include die-hard defenders of the rule of the Raj.