IELTS Academic Reading Practice Test 503

Of all the technologies the Romans introduced across their empire, the one that contributed most to everyday comfort in a cold climate was concealed beneath the feet. The hypocaust, whose name comes from Greek words meaning heat from below, worked by passing hot air and smoke from a wood fire through cavities built into the floors and walls of a building, so that the whole structure acted as a radiator and warmed every room above and beside it. It is best documented in the public bath houses of the empire, but it was also installed in private residences and in military fortifications.

The heart of the system was the furnace, or praefurnium, a brick-lined chamber at ground level, usually built against an outer wall. Positioning it there allowed the stoker to replenish it with wood without walking through the heated rooms and without admitting cold air through the door. Wood was the customary fuel, and the fire had to burn continuously for several hours before the baths opened. The mouth of the furnace was deliberately small, since a wider opening admitted excessive cold air and wasted fuel.

The space beneath the floor was made by raising it on rows of short pillars known as pilae. Each pillar was a stack of square tiles or circular bricks bedded in mortar and usually less than a metre high, and the rows stood close enough together to carry the weight of the floor above and of the bathers and the water standing upon it. On top of them the builders laid a bed of mortar and then the finished surface, which might be plain stone or coloured mosaic. The result was a floor that accumulated heat and released it gradually into the room.

Heating the floor alone would have left bathers with warm feet and cold shoulders, so the gases were also drawn up inside the walls. Builders set hollow box tiles into the wall structure, leaving a gap behind the plaster, and hot gases rising from the space under the floor passed through these channels before escaping through flues at the top of the wall or in the roof. The effect was a room warmed on several sides simultaneously, which is why bath houses could reach temperatures that visitors from cooler provinces considered almost unbearable.

Designing such a building required considerable expertise. The floor had to carry the weight of bathers and water yet stay light enough to warm quickly, and smoke was a continual hazard wherever the flues were badly positioned. Vitruvius, whose treatise On Architecture is the only complete Roman work of its kind to survive, set out rules for a suspended floor that would not crack under heat. He advised that the furnace be placed so that the hottest gases should reach the room that needed them most.

Hypocausts were expensive, and for that reason they also carried social significance. A private residence with underfloor heating announced that its proprietor could afford both the structure and the fuel. In the colder provinces, where warmth was a necessity rather than a luxury, villas often show a small suite of heated rooms attached to a larger unheated building, and Roman Britain has produced many well-preserved examples of the arrangement.

The operating costs were considerable: a large bath house burned wood for hours at a time, and the fuel had to be cut, dried and stored in advance, which meant carts and labour. Someone, in most households an enslaved worker, had to stay with the furnace to feed it and rake out the ash. These expenses, rather than any technological deficiency, explain why underfloor heating never became universal. The system remained a feature of public baths, wealthy houses and military sites, where the expense served a purpose.

Roman writers noticed both the comfort and the nuisance. Seneca, who lodged above a bath house, complained in a letter about the sounds that rose through his floor, among them the grunts of men exercising, the shouts of the masseur, the splashing of bathers and the constant roar of the furnace at all hours. Others remarked on the fiercest rooms, where the floor could be uncomfortable under bare feet. It produced rooms that were very hot rather than evenly warm.

When Roman authority in western Europe collapsed, the money, fuel and specialised skills that had sustained large bath complexes disappeared with it. Hypocausts fell out of use, and although heated floors of a simpler kind reappeared later in monasteries, the channels behind the walls were abandoned. Builders in cold countries turned instead to open fires and, eventually, to stoves and chimneys, which warm the air directly and need no cavity beneath the floor.

Contemporary understanding of the hypocaust derives principally from excavation. Archaeologists recognise heated rooms from the surviving stacks of pillars, from layers of ash and charcoal and from box tiles still embedded in fallen walls. In a few locations systems have been rebuilt and tested experimentally at full size. These experiments confirmed that a well-built hypocaust could raise the temperature of a room well above that of the outside air and hold it for hours. What the Romans achieved was not central heating in the modern sense, but proof that comfort can be built into a structure itself.

Children play in every human society that has ever been described, but what they play at, with whom and for how long varies enormously. Researchers usually define play as activity that is chosen freely, is enjoyable in itself and has no obvious purpose beyond the doing of it, and by that definition almost any behaviour can become play. A group of boys chasing each other across a yard may be practising skills, settling a hierarchy or simply enjoying the noise. The difficulty of separating play from work, ritual and learning is one reason why comparisons between cultures are so hard to make, and why confident generalisations about childhood tend to collapse on close inspection.

The study of play began in Europe and North America, and its early assumptions reflected that origin. Observations in nurseries in the 1930s produced a famous sequence in which children were said to move from playing alone, through playing alongside others, to genuinely cooperative play with shared rules and roles. For decades this sequence was treated as a natural stage of development. It rested, however, on small numbers of children in a handful of urban, middle-class settings, and later researchers found that the order and the timing of the stages differed widely elsewhere. In some places cooperative play appeared early; in others it was rarely seen at all.

The first large comparative study of childhood was carried out in the 1950s and 1960s, when teams of researchers lived for about a year in six communities on three continents and recorded what children actually did from morning until night. In most of those communities, children spent much of the day in mixed groups of ages, and older children were responsible for younger brothers, sisters and cousins. Play happened in the gaps between duties. Adults rarely organised games for children; the games were handed on by the children themselves, from the oldest to the youngest. A five-year-old minding a toddler was not free to wander, and the games that flourished were those that could be interrupted at any moment and taken up again later.

In farming and herding communities, children are often drawn into real work early. Anthropologists have described four- and five-year-olds fetching water, scaring birds from crops or watching animals: tasks that matter to the household and that children see adults performing every day. Play in such settings frequently imitates adult activity, with miniature tools, model animals and games of cooking or building. Some researchers describe this as rehearsal for adult life; others point out that the children themselves treat it as fun, and that the imitation is rarely exact. What is clear is that play and work are not kept apart as they usually are in a modern school day.

Pretend play has attracted particular attention. It was once assumed to be a universal feature of childhood and a necessary step in the development of language and reasoning. Surveys of the ethnographic literature have made this claim harder to sustain. In some communities adults neither provide toys nor join in fantasy, and children's pretending is brief and private; in others, elaborate imaginary worlds occupy hours. One attempt to explain the difference links it to the number of adults who play with children, another to the availability of manufactured toys. Neither explanation has been tested widely enough to settle the question, and both may be describing the effect rather than the cause.

Schooling reshapes play. Where children spend their days in classes organised by age, their playmates are mostly the same age, and games with elaborate rules and clear winners become possible and popular. Organised sport, music lessons and adult-run clubs fill hours that in other societies belong to the children themselves. The arrival of a school in a village can therefore change play within a single generation, and it is often difficult for researchers to separate the effects of schooling from those of the wage work, roads and shops that usually arrive with it.

Adults' ideas about danger also shape what children do. In some societies children of six move freely through the settlement and beyond it, and the risks they meet are accepted as part of growing up. In others an adult is present at almost every moment. Between these extremes lie most families, adjusting their rules to the street, the hour and the child. The difference is not simply one of wealth: a poor rural community may give children more independence than a rich city, but a crowded city with fast traffic may restrict them severely whatever their families can afford. What adults fear, as much as what children want, determines the space in which play happens.

How much confidence should we place in these comparisons? The evidence is uneven. Studies differ in method, in the age of the children observed and in what counts as a play episode. Most detailed studies come from a small number of regions, and a researcher's presence inevitably alters what children do: they may perform for the visitor or hide from the visitor. Sample sizes are often tiny, and words such as play carry different meanings in different languages. Above all, culture is entangled with schooling, work, housing and income, so a difference attributed to culture may have quite another cause. The variety is real, but its explanation remains largely a matter for argument.

Few decisions in family life look smaller and feel larger than whether a seven-year-old may walk to school without an adult. In much of Europe and North America the answer has changed within two generations. Transport researchers use the term independent mobility to describe the freedom a child has to move about without supervision, and surveys in several countries show that this freedom has shrunk sharply since the 1970s: children are now driven further, escorted more often and allowed to roam a smaller area than their parents were at the same age. Parents who were sent out alone at six now arrange lifts for children of ten. The change is not the result of any single decision by any single family. It has happened gradually, through a thousand small judgments about traffic, weather, neighbours and time, and it is the ordinary background against which the question in the title has to be answered.

The argument for letting children go is not mainly about exercise, though walking does provide it. It is about the skills that only practice can give. Finding one's way through a neighbourhood, judging whether a gap in the traffic is wide enough, deciding what to do when a plan goes wrong: these are learned by doing them, and they are learned imperfectly, in small errors, at an age when errors are still cheap. A child who has never crossed a road alone has had no chance to judge speed. Researchers who study children's independent mobility report that those given more freedom tend to be more confident about navigating unfamiliar places and more willing to take measured risks. The evidence is mostly correlational, however: families who grant freedom differ from those who do not in income, housing and outlook, and it is hard to show which factor produces which effect.

Against this stands a simple and serious objection. Roads kill and injure children, and the streets around schools are among the most dangerous places many of them will ever encounter. In high-income countries traffic is one of the leading causes of death among older children, and the risk is not spread evenly. Children in poorer districts are more likely to live beside fast roads, to lack safe crossings and to have no quiet alternative route. Parents in such districts are asked to weigh a developmental benefit against a danger they can see from their window. A policy that urges parents to send children out alone sounds very different in a leafy suburb with wide pavements and slow traffic than on a main road where cars pass at speed. Critics of the independence argument point out that the people who advocate it are usually those whose own streets are safest.

Fear of strangers plays a larger part in parents' thinking than the statistics justify. Serious harm from a stranger is rare, and children are far more likely to be harmed by someone they know. It also influences how far children are allowed to go, even where the streets are quiet. Yet the fear is not irrational in the narrow sense: it is sustained by intense media coverage of a small number of terrible cases, and by a culture in which a parent whose child comes to harm is held personally responsible. Several commentators have argued that this combination of a tiny risk, vividly imagined, and a heavy weight of blame explains more about the decline in independent mobility than any actual increase in danger. What the argument does not show is that the fear can simply be reasoned away.

If parents are not being foolish and children are not being reckless, the problem may lie elsewhere. A child's journey is shaped by decisions that no family makes: where schools are built and how pupils are assigned to them, the width of pavements, the speed limit on residential streets, the number of crossings and the design of junctions. No amount of parental courage will put a crossing where there is none. A comparison of children in England and Germany carried out in the 1990s found that German children were allowed to travel alone at considerably younger ages than English children, in a country where cycling and walking were better provided for. Some cities have since tried to change the environment rather than the child, closing the streets around schools at opening and closing times or organising walking buses, in which an adult accompanies a group of children along a fixed route.

My own view is that children should be allowed to walk to school alone, and that most of them should be doing so by the later years of primary school, unless the route is genuinely dangerous. The reason is not that the risks are imaginary but that the alternative carries risks of its own: a childhood in which every journey is supervised gives little practice in judgement, and builds a habit of dependence. This is a case for gradual independence rather than sudden freedom, and for changing the streets rather than lecturing parents. The child who has walked the same route a hundred times with an adult, then a few times ahead of the adult, is not being thrown into danger; the child is being taught to read it. The reasonable question is not whether children should go out alone, but what adults are prepared to do to make going out alone ordinary.