IELTS Academic Reading Practice Test 84

For centuries, the loss of ships close to shore was accepted with a kind of fatalism. Ordinary shore boats were occasionally used in rescue attempts, but they were heavy, difficult to launch in rough weather and easily swamped. Sailors and passengers often drowned within sight of land because no vessel could reach them safely, particularly on exposed coasts such as those of Northumberland, Norfolk and Cornwall. In the late eighteenth century, however, inventors and coastal communities began to ask whether a boat could be designed specifically for rescue work.

Lionel Lukin, a London coachbuilder, is usually credited with producing the first craft built explicitly as a lifeboat. In 1785 he patented an 'unimmergible' boat that contained built-in buoyancy chambers and cork, together with a heavy iron keel that helped it remain upright. Lukin had adapted a Norwegian yawl for the purpose, and he suggested that such boats should be stationed at dangerous locations. The boat was tested on the Thames and later stationed at Bamburgh on the Northumberland coast. Although Lukin's invention did not spread widely, his principle of providing reserve buoyancy became fundamental to later lifeboats.

Henry Greathead, a boatbuilder in South Shields, produced the first boat commonly called a lifeboat to see regular service. In 1789 a local committee commissioned him to build a rescue boat after a shipwreck in which many people died within sight of the town. Built in 1790 and named the Original, the boat was a double-ended wooden rowing vessel about ten metres long. It was fitted with cork for buoyancy and protected by a cork fender along the outside, and carried a crew of up to ten oarsmen. The Original was stationed at the mouth of the River Tyne and proved itself in many rescues. It was widely copied and served as a model for later designs, though it was not self-righting.

Before national coordination, rescue arrangements were local and inconsistent. Some coastal towns kept a boat, but many did not, and the boats varied widely in quality. Maintenance depended on voluntary subscriptions and the interest of individual patrons, so a boat could be left rotting on a beach while a neighbouring community had no service. Early lifeboats were open boats, so their crews were fully exposed to wind and sea. They could capsize, and if a boat filled with water it became useless unless it was bailed out quickly.

A national response began in 1824, when the National Institution for the Preservation of Life from Shipwreck was founded in London. The institution, now the Royal National Lifeboat Institution, aimed to provide lifeboats and rocket rescue apparatus around the coasts of Britain and Ireland. It drew support from philanthropists and coastal communities, and gradually brought existing local lifeboats under a single national system with shared standards and regular inspections. By the middle of the nineteenth century the number of stations had grown, though gaps remained in the west of Ireland and the north of Scotland.

The most important design advance of the nineteenth century was the self-righting lifeboat. Builders discovered that by placing heavy ballast low in the hull, fitting airtight compartments at the ends, and shaping the hull with raised ends and a deep keel, they could make a boat return upright after being knocked over. This feature saved the lives of many volunteer crews, and self-righting designs became standard for smaller pulling and sailing lifeboats; the principle was soon adopted by rescue services in other countries.

Propulsion changed only slowly. For decades lifeboats were rowed by oarsmen, with sails added on larger models for longer journeys. Some early self-righting boats also carried a small sail to help them return to shore against the wind. The first motor lifeboats appeared in the early twentieth century, and although their early engines were not always reliable, motor power gradually replaced both oars and sails. By the later twentieth century all-weather lifeboats were motor-driven, while smaller inshore craft used outboard engines.

Alongside the boats themselves, many stations kept equipment for reaching crews without sending a boat through the surf. The most common was the rocket line, a light rope fired by rocket or mortar from the shore to a stranded vessel, which could then be used to carry survivors to land on a breeches buoy. This apparatus was used when a boat could not safely approach a wreck, and it saved many lives on flat and sandy coasts where launching a lifeboat through heavy surf was especially difficult.

Modern lifeboats bear little resemblance to the open wooden pulling boats of the early 1800s. They are built from reinforced plastics or metal alloys, have enclosed wheelhouses, carry radar, satellite navigation and electronic communication equipment, and can reach speeds unimaginable to earlier rescuers. Despite these changes, the basic principle described by Lukin—reserve buoyancy supplied by air-filled spaces or foam—remains central. Modern crews are still volunteers, and many stations depend on local fundraising.

Lifeboats are perhaps the oldest form of organised emergency service still in operation. The combination of volunteer crews, local knowledge and continuously improved engineering has saved countless lives across more than two centuries. Although ships and navigation have been transformed, the problem that gave rise to the first lifeboats—how to reach people in danger close to shore—has not disappeared, and the boats built for that purpose continue to evolve.

A black hole is an object so dense that light cannot escape from it. Because no light reaches an outside observer, the object itself is invisible, and the region of no return, called the event horizon, cannot be seen directly. To take a picture of a black hole, astronomers must detect the glowing gas and dust that orbit it, which appear as a bright ring around a dark shadow. The difficulty is resolution: the nearest supermassive black hole, at the centre of our own galaxy, is tens of thousands of light years away and appears smaller in the sky than a coin on the Moon. No single telescope can resolve such a tiny object, so scientists needed a new approach.

The solution was very long baseline interferometry, a technique that combines signals from radio telescopes located thousands of kilometres apart. When the telescopes observe the same source simultaneously, their data can be merged to simulate a single telescope as large as the distance between them. This is not done by physically connecting the dishes; instead, the signals are recorded with extremely precise time stamps and later brought together for processing. The resolving power then depends on the separation of the telescopes, not on the size of any one dish, allowing a network to act as a virtual telescope the size of the Earth.

The Event Horizon Telescope, or EHT, is an international collaboration that applies this technique at millimetre radio wavelengths. It links radio observatories in locations such as Hawaii, Arizona, Mexico, Chile, Spain and the South Pole. Observations at these short wavelengths can peer through the hot gas that surrounds a black hole, but they also require exceptionally dry, stable atmospheric conditions. The participating telescopes must be aimed at the target at precisely the same time, and the weather must be good simultaneously at all sites. For this reason, the collaboration plans its observing campaigns years in advance and remains on standby for suitable nights.

In April 2017 the EHT carried out its first full observing campaign, pointing its telescopes at the supermassive black hole at the heart of the galaxy M87, about 55 million light years from Earth. For several nights the team collected data at several frequencies, recording the radio waves on banks of hard drives. Each station produced so much data that the drives could not be sent over the internet; they were carried by aeroplane to central processing centres in the United States and Germany. The total volume of data ran to several petabytes, roughly the equivalent of many years of high-definition video.

Once the hard drives arrived, the slow work of correlation began. Specialised supercomputers aligned the signals from each pair of telescopes, correcting for differences in arrival time caused by the Earth's rotation and by tiny variations in the clocks at each site. This process produced a set of measurements from which an image could be reconstructed. Because the network does not cover the entire Earth, the data are incomplete, and several different images can be consistent with them. The team therefore used imaging algorithms to search for the simplest image that explained the observations, while a separate group performed blind tests to guard against bias.

The result, revealed to the public in April 2019, was a ring of bright emission surrounding a dark central region. The dark part is the shadow of the black hole, about 40 microarcseconds across, and the bright ring is formed by hot gas swirling around it. The image matched the predictions of Einstein's general theory of relativity with remarkable precision, confirming that the object in M87 is indeed a black hole with a mass about 6.5 billion times that of the Sun. Scientists described the image as a landmark in both astronomy and physics, and it quickly became one of the most widely reproduced scientific images of the decade.

Beyond the image itself, the EHT data have allowed researchers to measure the size of the shadow, which depends on the mass and spin of the black hole, and to study the behaviour of the glowing gas in the accretion disk. The observations also provide a new way to investigate how some black holes launch powerful jets of material at close to the speed of light. The EHT continues to observe M87 and other targets, and each new campaign adds more telescopes and more frequencies, improving the resolution and sensitivity of the virtual array.

A second target was Sagittarius A*, the black hole at the centre of our own Milky Way, which is much smaller and varies rapidly. Imaging it proved difficult because its appearance changes over minutes rather than days, and the collaboration released its picture only in 2022, after developing new methods to cope with that variability. As more observatories join the network, including space-based antennas in the longer term, the images should become sharper and more detailed. The EHT has shown that an Earth-sized telescope is not a fantasy, and its techniques are now being applied to other astronomical problems.

A long commute is often listed among life's most unpleasant experiences. Commuters complain of crowded trains, congested roads and wasted hours. My own view is that the popular image of commuting as uniformly harmful oversimplifies the evidence. The effect of a journey to work depends on how long it takes, the mode of travel, the predictability of the journey and the circumstances of the worker. This complexity explains why surveys of commuters often produce contradictory results, with some drivers reporting satisfaction and some walkers reporting discomfort.

Research on life satisfaction has consistently found a negative association between commuting time and reported well-being. People with long commutes tend to say they are less happy with their lives, and this relationship remains even after controlling for income, age and family situation. However, the size of the effect is small when compared with other influences such as unemployment, poor health or separation. A daily commute of an hour each way is a burden, but it appears to be a moderate one rather than a source of constant misery. Early studies often treated commuting time as a simple cost, but later work has tried to identify which journeys are most harmful.

The mode of travel matters a great deal. Driving in heavy traffic is often the most stressful way to reach work, because the driver must maintain continuous attention, cannot easily use the time for other purposes and may be delayed unpredictably. In contrast, walking or cycling tends to be associated with neutral or even positive effects, because physical activity and time outdoors can improve mood. Rail commuters occupy a middle position: trains are not physically demanding, but overcrowding, delays and the need to stand can cause real discomfort. A delayed train with no seating can be as unpleasant as a traffic jam. The same journey length can therefore have very different consequences depending on how it is made.

Predictability and control appear to be central. When a commute is reliable, workers can plan around it, and the journey can become a defined period between home and work. When it is unpredictable—when a road may be blocked or a train cancelled—the uncertainty adds a psychological cost that goes beyond the lost minutes. Studies using travel diaries have found that unexpected delays are remembered as among the most stressful events of the working day, and that their effects can spill over into performance and mood at home. Thus it is not simply time spent travelling that matters, but the sense of being in control of that time. The uncertainty surrounding a journey can be as damaging as the journey itself.

Long commutes also reduce the time available for other activities, and this may be their main mechanism of harm. Workers who spend two hours a day travelling have less time for sleep, exercise, preparing food and seeing family and friends. These are the activities that protect well-being, so the loss is indirect but real. Some researchers have argued that the negative association between commuting and life satisfaction is largely explained by the crowding out of sleep and social contact rather than by the journey itself. If this is correct, then any policy that gives commuters back even a portion of their day may produce disproportionate benefits. Time-use surveys show that long commuters sleep less and exercise less, and these missing hours are not fully recovered at weekends.

Yet the picture is not entirely negative. Some commuters deliberately use the journey as a transition period between work and home, a time for reading, planning or listening to podcasts. A predictable train journey can provide a rare period of solitude in a busy day. A small number of long-distance commuters even report that they value the time as a chance to decompress from work. These benefits depend heavily on comfort and reliability, and they are much easier to obtain on uncrowded trains than on congested motorways. Being able to sit, read or rest turns some journeys into a form of buffer time that would otherwise have to be found elsewhere in the day. Nevertheless, they show that commuting is not automatically wasted time.

The policy implications are fairly clear. Reducing the need for long commutes—through remote work, flexible hours and housing that places workers closer to jobs—is likely to improve well-being. Improving the quality of the journey matters too: reliable public transport, safe cycling routes and uncongested roads all reduce the psychological cost of travel. Some employers have experimented with paying for transport improvements or allowing employees to start and finish at times that avoid peak crowding. Some governments have begun to include commuting time in assessments of urban well-being, and a number of cities have invested in cycling networks to shorten door-to-door times. In my view, such measures are not luxuries but practical responses to a genuine source of daily stress.

It would be a mistake, then, to declare that commuting is always harmful or always beneficial. The evidence points to a more modest conclusion: long, unpredictable car commutes are generally bad for well-being, while shorter, active or comfortable journeys are largely neutral and may occasionally be positive. Because commuting is a regular part of so many lives, even small improvements can accumulate across years. For individual workers, choosing a home closer to work or negotiating flexible hours may be among the most effective steps. The goal of policy should therefore be to reduce the most damaging journeys and to make the rest as predictable and comfortable as possible.