GMAT Verbal 30: How Reading Comprehension Works — Passages, Question Sets and a Reading Map

In the 1420s, Ulugh Beg, the ruler of Samarkand and a grandson of Timur, built one of the largest observatories of the medieval world on a hill outside the city. Its central instrument was not a telescope — telescopes would not be invented for nearly two centuries — but an enormous meridian arc: a curved track cut into the hillside along the north–south line, with a radius of roughly 40 metres. The size was the point. On an instrument that large, a single degree of arc stretched across a long section of the track, so observers could read the position of the Sun or a star far more finely than on the small brass instruments of the time.

The results justified the effort. The astronomers working with Ulugh Beg produced the Zij-i Sultani, a set of astronomical tables that included a catalogue of about a thousand stars. Their measurement of the length of the year differed from the modern value by less than a minute.

The observatory did not long outlive its founder. After Ulugh Beg was killed in 1449, the building was abandoned and gradually destroyed, and its location was forgotten. Only in 1908 did the archaeologist Vasily Vyatkin, guided by a historical document, uncover the remains of the arc, which visitors to Samarkand can still see today. The tables had travelled further than the building: copies circulated widely, and a Latin translation of the star catalogue was published in Oxford in 1665.

Before the mid-1950s, loading a cargo ship was slow and costly work. Goods arrived at the docks in sacks, barrels and crates of every size, and teams of dockworkers carried them aboard piece by piece, a process that could keep a ship in port for days. Theft and damage were common, and the cost of handling cargo at both ends of a voyage often exceeded the cost of the voyage itself.

In 1956 a trucking entrepreneur named Malcolm McLean sent a converted tanker, the Ideal X, from Newark to Houston carrying 58 metal containers that could be lifted directly from truck to ship. The idea was simple: rather than handling each item, handle one standard box. McLean later estimated that loading the Ideal X had cost about 16 cents per ton, compared with roughly $5.86 per ton for loose cargo.

The savings did not arrive all at once. Containers paid off only when ports, ships, trucks and railways were all built to handle the same box, and agreeing on standard sizes took years of negotiation. Many ports that refused to invest in cranes and storage yards lost their trade to rivals that did. But once the system was in place, the cost of moving goods between continents fell so far that it became practical to make a product's parts in several countries — one reason economists often list the container among the inventions that made modern globalisation possible.