IELTS Academic Reading Practice Test 254

The Taj Mahal stands on the bank of the river Yamuna at Agra, in northern India, and was built by the Mughal emperor Shah Jahan as a tomb for his favourite wife, Mumtaz Mahal. She died in 1631, a short time after the birth of her fourteenth child, at Burhanpur, a town far to the south where the emperor was then campaigning. The court went into mourning, and work on the tomb began the following year at Agra, then the imperial capital.

The site chosen was on the south bank of the river Yamuna, a short distance downstream from the fort where the emperor held court. The land belonged to a nobleman and was exchanged for other property. The position was not accidental. In Mughal garden design the setting of a tomb was considered part of the monument itself, and the river gave the complex one of its most spectacular effects, with the building rising behind a long channel of water. On the opposite bank a further garden was laid out on the same axis.

The design is usually credited to a court architect, Ustad Ahmad Lahauri, though no contemporary document names a single designer, and most historians now describe the work as a collaboration between architects, calligraphers, stone-cutters and gardeners. Its designers drew on earlier Mughal tombs, above all the tomb of Humayun in Delhi, which had established the pattern of a domed building set in a walled garden.

White marble was brought from Makrana, a site in Rajasthan several hundred kilometres to the west, and hauled to Agra by teams of oxen and elephants. A French merchant, Jean-Baptiste Tavernier, who saw the work in progress, reported that 20,000 men were employed; the court's own records give no such figure, and the number must in any case have varied with the season. The names of the individual craftsmen have almost all been lost. The inscriptions preserve those of a few calligraphers and of the man who supervised the work, but say nothing about the thousands who cut and laid the stone.

The tomb rests on a vast square platform raised above the riverbank. Building proceeded from the outside inward, and the platform was filled with rubble and brick before the marble casing was applied. A famous story holds that the brick scaffolding was left for the poor of Agra to take away, and that Shah Jahan then ordered it to be dismantled slowly so that it never had to be rebuilt. There is no contemporary evidence for the tale, which is probably an invention of later guides.

Four minarets stand at the corners of the platform, each more than forty metres high. They lean slightly outward from the tomb. The usual explanation is that this would make them fall away from the dome in an earthquake, although some engineers have suggested that the lean is simply a result of the way they were built. Between them rises the great double dome, an outer shell of marble above an inner ceiling, a device that allows the dome to look far larger from outside than it does from within the chamber.

Above the platform the surfaces are covered with ornament. Hard semi-precious stones were cut into shape and set into recesses in the marble, a technique known in Italy as pietra dura. Twenty-eight different kinds of stone are said to have been used, some of them brought from Persia or Afghanistan. The calligraphy, mostly verses from the Quran, is attributed to a Persian-trained master, Amanat Khan. On the great gateway the letters of the inscription grow larger the higher they are placed, so that a visitor looking up sees them all as the same size. The device corrects for the way distance shrinks writing.

In the centre of the platform the tomb chamber is an octagonal room, lit only by light filtered through carved screens. Round the two cenotaphs runs a pierced marble screen, itself a masterpiece of the stone-carver's art. The actual graves lie in a vaulted crypt beneath the floor. The contrast with the glare of the terrace outside makes the inlaid flowers of the cenotaphs seem to glow.

Shah Jahan was deposed by his son Aurangzeb in 1658 and spent the last years of his life imprisoned in the fort at Agra. From there the tomb of his wife was visible across the river. When he died in 1666 he was buried beside her, the only later addition to the chamber. In the eighteenth century the building suffered from neglect and from the disorder that followed the collapse of Mughal power, and parts of the complex were plundered.

Early in the twentieth century the viceroy, Lord Curzon, ordered a thorough restoration. His work saved the building from decay, but it also changed it: the garden was replanted with lawns and flowerbeds in an English style, and lamps and railings were introduced. Since then the greatest threat has come from pollution. Exhaust from traffic and smoke from nearby industry have stained the white marble, and restorers have periodically applied a paste of clay to draw the dirt out of the stone. The monument became a World Heritage Site in 1983, and vehicles are now banned from the area around it.

An astrolabe is a flat, circular instrument, usually of brass, that represents the sky above a particular place at a particular latitude. Most examples are between fifteen and forty centimetres across, small enough to be carried but large enough for their scales to be read. Suspended by a ring from the thumb or a hook so that it hangs vertically, the instrument can be used to measure the height of the sun or a star above the horizon. From that measurement, and the date, a skilled user could read off the time of day or night, the hour of sunrise and the positions of the brightest stars. In the Islamic world it also gave the times of prayer and the direction of Mecca. The name comes from Greek words meaning 'star-taker', and for many centuries the instrument was the most sophisticated portable device in existence.

The mathematics behind the astrolabe is the stereographic projection, in which points on a sphere are mapped onto a flat surface. Greek geometers had worked this out long before anyone built an instrument to exploit it, and the earliest surviving treatise describing an astrolabe is attributed to John Philoponus, a Christian philosopher in Alexandria who wrote in the sixth century AD. Whether an actual instrument existed earlier is disputed. Some historians argue that the treatises describe devices that were never made, while others point to references in earlier literature and conclude that the astrolabe was already familiar to astronomers in late antiquity.

It was in the Islamic world, from the eighth century onwards, that the instrument was developed most intensively. Astronomers in Baghdad and later in Persia, Syria and Spain added scales and star tables and adapted the design to the latitudes of their cities. Because it could serve both astronomy and religious observance, it attracted the patronage of rulers, and the finest examples are objects of great beauty, engraved with names, dates and dedications. Several hundred medieval astrolabes are known to survive, many of them signed by their makers, which gives historians a dated sequence of objects to study — an advantage they rarely have.

The instrument has a small number of components. The circular body, or mater, holds everything else. Around its rim runs the limb, a graduated scale marked in degrees. Onto the mater are laid a set of plates, each engraved with the lines of the sky for one latitude. Over them turns the rete, an openwork map of the brighter stars fitted with small pointers. A sighting rule, the alidade, pivots at the centre and is used on the back, where further scales are engraved. Among these is the shadow square, a simple grid that allows the user to calculate the height of a tower or the distance of a ship by comparing similar triangles.

The weakness of the standard design is that it is tied to a place. A plate cut for the sky over Cairo is useless in Isfahan, and a traveller needed either a set of plates or a different instrument. In the eleventh century the astronomer al-Zarqali, working in Toledo, devised a form that could be used at any latitude, and other solutions were attempted in Persia and Byzantium. At sea the problem was attacked differently. The mariner's astrolabe, developed by Portuguese navigators in the fifteenth century, discarded almost everything except a heavy graduated ring and an alidade, so that it could be read from the deck of a moving ship without being blown out of alignment.

Museum collections, then, are misleading in a particular way. The astrolabes that survive are mostly the expensive ones: brass, finely engraved, made for princes, scholars and collectors. The plain wooden or roughly cast instruments that a working surveyor or a ship's officer might have owned were used until they wore out or were melted down. A history based only on surviving objects therefore describes the taste of patrons as much as the practice of astronomy. Written sources have their own bias, since a treatise sets out what an instrument should be able to do rather than recording what its owner actually did with it.

On this point historians disagree. One view holds that the astrolabe was, for most of its history, a specialist's tool and a status object, and that everyday timekeeping relied on simpler devices, on tables and on the position of the sun. The other view points to the sheer quantity of teaching material. Geoffrey Chaucer wrote a treatise on the astrolabe in 1391 for his young son, in English rather than Latin, and the text assumes that a boy of about ten can be taught to set the instrument and take a reading. If a child could learn it at home, it cannot have been only a decoration.

The star pointers on the rete have given historians a problem of their own. Identifying which star each pointer represents means comparing it with the star catalogues that astronomers of the period used, and where two pointers lie close together the identification may be uncertain. Instruments were also repaired over the centuries, and a rete or a plate may be later than the rest. Every such alteration has to be detected before an astrolabe can be dated, which is why the study of these objects needs both astronomy and an eye for metalwork.

Mechanical clocks, the telescope and finally the sextant took over the astrolabe's tasks one by one, and by the eighteenth century it was obsolete as a working instrument. What it left behind was a habit of mind: the idea that the whole sky could be drawn on a disc and carried in the hand, and that careful measurement could be made anywhere. Major collections are now held in European museums, where the instruments are valued less as antiques than as records of a mathematical culture that stretched from Alexandria to Toledo.

There is a particular kind of disappointment known to anyone who works in a public archive. You order a file that appears in the catalogue, wait for it to be fetched, and are handed a folder from which several pages have been removed. The catalogue still gives the file's title, but the contents have been judged unfit for you. Such gaps are rarely mentioned in debates about freedom of information, yet they mark the point at which a state's attitude to its own history becomes visible. They raise a simple question: how long should a government be allowed to keep its own papers from the people who paid for them?

Britain's answer has changed. Under rules introduced in 1967, most government files were opened at the National Archives after thirty years. In 2013 that period was cut to twenty. Because the change could not be applied all at once, the archive ran a transition under which two years' worth of records were released each year until the gap was closed. The United States works towards a twenty-five-year limit for most classified material, while some European states still hold records for thirty years or longer. Sweden, by contrast, has had a constitutional presumption of access since the eighteenth century.

The case for releasing files earlier rests on the purpose of an archive. Records exist to make power accountable, and accountability has a shelf life. A document showing that a minister ignored advice is of limited use to a parliamentary committee twenty-five years after the decision, when the minister has left politics and the policy has been abandoned.

The Hillsborough Independent Panel, which in 2012 published files about the deaths of ninety-six football supporters in 1989, showed how much can still be recovered from official records. It also showed how long the families had waited. For those families the documents mattered for one reason above all: they established who had been responsible.

Campaigners for open government go further. Their claim is that the length of the closed period is chosen not to protect anything that still matters but to allow embarrassment to fade. The officials who wrote the documents will have retired, the ministers who signed them will have left public life, and the argument that the papers would inflame will have been settled by other means. On this view, delay is not a security measure at all but a form of reputation management, paid for by the public.

Against this, senior officials make two arguments. The first concerns candour. Advice is only useful if it is frank, and officials will write for the file rather than for the minister if they believe that what they say will be read by journalists while they are still in their posts. The second concerns the people named in the papers: informants, witnesses and private individuals whose medical or financial troubles happen to have been recorded. Genuine security secrets, it is argued, are a small part of the total, but they are the part that cannot be released at any price.

Historians find the candour argument difficult to test and partly self-defeating. Officials already know the rule, so if secrecy guaranteed frankness they should already be writing frankly; the claim can only be examined by opening the files, which is precisely what is refused. The more serious complaint concerns interpretation. A record read thirty years later is a record without its witnesses: the civil servant who drafted it has died or forgotten, and the context in which a decision seemed sensible has disappeared. Delay does not merely postpone understanding; it can make understanding impossible.

There is also a practical problem that no change in the law can wish away. Paper files were finite and could, at a stretch, be read page by page. The records now being created are electronic, and their number is beyond any realistic process of individual review. Declassification at the scale required would depend on software, and software cannot judge whether a sentence endangers an informant. The temptation is therefore to withhold whole categories of material, or to release it so heavily redacted that it says nothing, a practice that produces the appearance of openness without its substance.

My own view is that the argument should move away from the length of the period and towards the question of who decides. A fixed maximum, whatever its length, is worth little if a department can extend it indefinitely without giving reasons. What is needed is a short default period and exemptions that expire rather than renew automatically. Decisions about what remains closed should be taken by an arbiter outside the department concerned, whether a judge or an independent commissioner with power to inspect the documents themselves. Where material must be withheld, the existence of the file and the reason for withholding it should still be published.

None of this removes the need for secrets. A state that published everything immediately would be unable to govern, and some of the arguments for caution are sound. But the balance has drifted too far towards the convenience of institutions. On balance, the harm that long delay does to public understanding seems to me greater than the harm that earlier release is likely to cause. Archive shelves are not neutral ground: what a government chooses to hide, and for how long, is itself a statement about what it thinks the public can be trusted to know.