IELTS Academic Reading Practice Test 491

Scattered across the rolling plateau of Xieng Khouang in north-eastern Laos stand thousands of stone vessels. Some are no bigger than a bucket; others are taller than a person. They are known simply as the jars, and the landscape they occupy has given the region its English name, the Plain of Jars. The jars are spread over hundreds of square kilometres, singly, in small clusters and in groups of several hundred. The nearest town, Phonsavan, was built in the 1970s to replace a provincial capital destroyed in the fighting, but the jars themselves are far older.

The jars are carved from stone. Sandstone, granite and limestone all occur among them, and a single group may contain vessels of several different rocks. Most have a hollowed body and a thick rim; many have a separate lid, now usually lying on the ground beside its jar. The largest reach about three metres in height and weigh several tonnes. Some of the rock does not appear to occur near the sites, so either the finished jars or the blocks from which they were cut were moved, sometimes over several kilometres. No one has established how the transport was managed, though levers, ropes and large teams of people are the usual guesses.

Local tradition has its own explanation. In the best-known version, the jars were made by a giant called Khun Cheuang, who had defeated an enemy and needed vessels in which to brew rice wine for the victory feast. A less cheerful story says that they were drinking cups for a race of giants who have since vanished. Neither account, of course, can be tested, but both explain something that archaeology finds awkward: the jars are far too large for any ordinary household purpose.

The first systematic attempt to explain the jars was made by Madeleine Colani, a French archaeologist working in what was then French Indochina. During the 1930s she travelled the plateau, recorded dozens of sites and opened excavations at several of them. Beneath and around the jars she and her team found human bones, teeth and fragments of skull.

She concluded that the jars were funerary urns, and that the ground in which they stood had served as a cemetery for communities whose identity could not be recovered from any written source. She published her findings in a long monograph in 1935. Her interpretation has been modified in detail but has never been replaced.

Archaeology on the plateau resumed on a larger scale in the 2010s, when a team led by researchers from Australia began excavating again. Their trenches produced more burials, some accompanied by grave goods such as pottery and bronze ornaments, and evidence of a settlement in the surrounding landscape. Radiocarbon dates from charcoal and bone have placed the burials broadly in the Iron Age, a period that in mainland Southeast Asia ran from roughly 500 BC into the early centuries AD. The dates are not tidy: samples from different sites scatter widely, and it remains unclear whether jars were made over several centuries or produced in a short burst of activity.

Whatever the jars meant to the people who made them, the plain later became one of the most heavily bombed places on earth. Between 1964 and 1973, during the war in neighbouring Vietnam, aircraft dropped more than two million tonnes of ordnance on Laos. Xieng Khouang province, where the North Vietnamese army moved troops and supplies, received a large share of it. Craters are still visible beside many of the jar sites, and some jars were cracked or overturned by the explosions. The plain was not a quiet backwater that archaeology could study at leisure; it was a battlefield that contained ancient monuments.

Not all of that ordnance exploded. Cluster bombs scatter dozens of small bomblets over a wide area, and a substantial proportion of them failed to detonate on impact. For decades afterwards, farmers, children and animals were killed or injured by devices that had lain in the soil since the 1970s. Clearance organisations have since removed large quantities of unexploded material, but the work is slow and expensive. At the sites that tourists visit, teams have cleared narrow corridors and marked them with white stones or painted lines; visitors are instructed to keep to these paths, and signs at the entrance show photographs of the objects that must not be touched.

In 2019 the United Nations Educational, Scientific and Cultural Organization granted the Megalithic Jar Sites of Xieng Khouang World Heritage status. The decision recognised both the jars themselves and the landscape around them, including quarries, burial grounds and the remains of the settlements to which the dead were taken. Of the more than ninety recorded jar sites, only a handful can be visited: Site 1 lies a short drive from Phonsavan and is the busiest, while Sites 2 and 3 require a walk of some distance across rice fields. Hotels, restaurants and guides in the province now depend partly on these visitors.

Much, however, remains unknown. Were the jars carved where the stone was quarried and then dragged to their positions, or were rough blocks shaped on site? Why are there so many groups, and what connected them? And why this plateau in particular? A monument that carries no inscription can still be read, but only slowly. The jars have outlasted the people who made them by two thousand years, and they have so far declined to say anything definite.

An iceberg is a block of freshwater ice that has broken away from a glacier or an ice shelf and is floating in the sea. The word itself comes from the Dutch ijsberg, meaning ice mountain. What strikes anyone who sees one at close range is the disproportion between the visible part and the whole. Ice formed from compacted snow is slightly less dense than the water of the ocean, and roughly nine-tenths of its mass therefore lies underwater. The smooth white peak that appears on postcards is a small fraction of a body of ice that may weigh millions of tonnes.

Icebergs begin as snow. On a glacier, snow that survives the summer is buried by the snow of the following winter, and as the layers pile up, the lower ones are squeezed into a granular substance called firn and eventually into solid ice. Air is trapped in bubbles as this happens, so glacier ice is a mixture of crystal and gas rather than a pure solid. Gravity then sets the whole mass moving downhill at speeds that may range from a few metres to several kilometres a year. Where a glacier reaches the sea, or where it pushes out over the water as a floating tongue, the ice at the front eventually breaks off. This process is known as calving.

Antarctica produces the largest icebergs because it is ringed by ice shelves, thick plates of glacier ice that extend over the sea while remaining attached to the land. When an ice shelf calves, the piece that breaks away tends to be enormous and flat, and it can drift for years before it breaks up. In March 2000 a section of the Ross Ice Shelf about 11,000 square kilometres in area separated and was named B-15; it was the largest iceberg ever recorded. Smaller fragments of it were still being tracked nearly two decades later. Ice shelves also act as a brake on the glaciers behind them, so their loss can allow those glaciers to flow faster towards the sea.

Icebergs are classified by shape, and the shapes reflect their origins. The tabular iceberg has a flat top and steep sides, and its length is more than five times its height; almost all of them come from ice shelves. A blocky iceberg is also flat-topped with steep sides, but it is shorter, with a length less than five times its height, and it usually comes from a glacier. Domed icebergs have rounded tops, pinnacled ones carry one or more sharp spires, and a wedged iceberg has a steep side on one flank and a sloping side on the other. The shape changes with time, since melting and collisions with other ice wear the edges away.

Once adrift, an iceberg goes where the water takes it. Because so much of the ice is submerged, currents exert far more influence on its course than wind does. Wind and waves nevertheless affect the smaller fragments, and can spin a berg slowly round. In the Southern Ocean, icebergs are carried eastwards by the Antarctic Circumpolar Current and gradually diverge northwards, where they melt in warmer water. In the North Atlantic, icebergs calved from the glaciers of Greenland are carried south along the coast of Canada by a cold current. The general circulation also bends their paths: on a rotating planet, moving water is deflected, and the deflection differs between the two hemispheres.

For ships, drifting ice is a serious hazard, and the best-known disaster it caused changed the law of the sea. When the Titanic struck an iceberg south of Newfoundland in April 1912 and sank, there had been no organised system for reporting ice in the area. The following year an international conference in London produced the first convention on safety of life at sea, and in 1914 an international ice patrol was set up to watch the shipping lanes. Its ships and aircraft now share the work with satellites, which can detect the position and size of icebergs over wide areas, and warnings are broadcast to shipping throughout the season.

Melting is not a simple matter of shrinking. An iceberg is worn away fastest at the waterline, where waves and relatively warm surface water cut a groove around it. As the groove deepens, the upper part loses support, and the whole berg may overturn, presenting a new and unpredictable profile to the sea. This is one reason why an iceberg that has been approached safely can become dangerous within hours. Icebergs are also not uniformly white. Ice that has been compressed under great pressure contains few air bubbles and absorbs red light, so it appears a deep blue; bands of such ice are often visible where a berg has broken along an old crevasse.

Icebergs matter to science as well as to navigation. As they melt they release material that had been collected by the glacier, including iron and other nutrients, and this can encourage the growth of phytoplankton in the surrounding water. Some researchers have therefore argued that large numbers of melting bergs affect the productivity of the ocean, though the size of the effect is disputed. The green tint seen in some Antarctic icebergs has been explained as iron-rich sediment from the bedrock, but other explanations have also been proposed. Engineers have repeatedly suggested towing icebergs to dry coasts to supply fresh water; the distances and the losses in transit have so far defeated every scheme.

Few questions in the museum world provoke as much disagreement as the disposal of objects. Every collection contains far more than any building can display, and every collection costs money to keep. When a museum faces a deficit, the temptation to sell something valuable that nobody has asked to see for thirty years can be considerable. The professional term for the process is deaccessioning, a deliberately neutral word for an act that many people regard as a betrayal. The argument is not really about money, though money usually starts it. It is about what a collection is for, and who, if anyone, owns it.

Those who oppose sale begin from the principle that a museum holds its collection in trust. Objects are acquired for the public, often with public money or with donations, and the people who gave them expected them to remain available. A sale is irreversible: once an object has gone to a private buyer, it may never be exhibited again, and it may leave the country altogether. Critics also point out that the proceeds of a sale rarely solve a financial problem for long. A museum that sells a painting to repair a roof will still need to repair the roof in twenty years, but the painting will not be there to sell a second time. Donors who watch their gifts go under the hammer may also prove harder to find in future.

Professional bodies have tried to draw a line. For decades the main associations of museums and art galleries in the United States required that the proceeds of any sale be used only to buy new works or to care for the collection, never to pay salaries, buildings or other running costs. A museum that broke the rule risked censure. In 2020, when galleries closed their doors and income collapsed, the leading association of art museum directors temporarily relaxed its guidance, allowing institutions to spend such money on the direct care of collections. The change was presented as temporary, but it showed how quickly a firm principle can bend.

Breaking the rule has sometimes been costly. In 2014 a museum in the English Midlands sold an ancient Egyptian statue from its collection, arguing that the money was needed for a building project. The sale raised a sum reported at the time as more than £15 million, but it also provoked an outcry. The museum's national accreditation was withdrawn, which affected its eligibility for certain grants and loans, and the statue's departure was treated by many in the sector as a scandal rather than a solution. The episode is now cited in almost every discussion of disposal, usually as a warning.

Defenders of disposal reply that the trust argument proves too much. A collection is not a warehouse, they argue, and an object that is never displayed, never studied and never requested by a researcher serves nobody. Many museums can show only a small proportion of what they own; the rest sits in climate-controlled stores that consume staff time and energy. Storage is not free, and space given over to unused objects cannot be used for anything else. If a work duplicates another, falls outside the institution's stated purpose, or can be sold to a museum that will actually exhibit it, the argument runs, keeping it is not caution but hoarding. On this view a collection should be treated as a living thing, pruned so that the remainder can be looked after properly.

The difficulty with this reasoning is that it has no natural stopping point. A museum that has sold one object to fund a display can sell another to fund a lift, and a third to avoid making a member of staff redundant. Each decision may look reasonable on its own, and the cumulative effect is a collection quietly hollowed out. Nor is the money always reinvested: in practice, proceeds that begin as capital have a way of becoming income. A rule that forbids sale altogether removes this danger; a rule that permits it in exceptional cases depends entirely on the judgement of the people who are under pressure to sell.

Some of the obstacles to sale are legal rather than ethical. In Britain, the British Museum is barred by statute from disposing of objects except in narrow circumstances, most of them involving duplicates or items unfit to be kept, and proposals to amend the law have repeatedly failed. Meanwhile the pressure to return objects to their countries and communities of origin has grown, and many institutions have begun to transfer ownership without payment. Where an object was taken, in the colonial period or later, from a community that never agreed to part with it, a sale compounds an old injustice, since the community receives nothing while the museum is paid.

My own view is that sale should be permitted, but rarely and under conditions strict enough to make the exception uncomfortable. The money should be ring-fenced for the collection itself, never for the general budget. Any proposal should be published in advance, with the reasons for it and the alternatives considered, and it should be subject to independent scrutiny, not merely approved by the same trustees who face the deficit. Where an object is of interest to another public institution, transfer should be preferred to auction. Above all, the decision should be justified by what the collection gains, not by what the museum loses if it does not sell. Judged by those tests, most sales that have caused scandal would not have happened.