Ejercicios de comprensión lectora - Inglés avanzado | Ejercicios de funciones discursivas - Inglés avanzado | Prácticas de comprensión lectora

Ejercicios: Textos científicos divulgativos en inglés


Volver al índice de ejercicios de reading

La misión de los textos científicos divulgativos es acercar contenidos científicos al público general, sin utilizar el lenguaje técnico o académico propio de las publicaciones de especialidad. He encontrado un texto en The New York Times sobre las pirámides egipcias que os propongo leer a continuación en una versión adaptada (podéis encontrar el artículo entero en este link: Did the Great Pyramids’ builders use concrete?).

Did the Great Pyramids’ builders use concrete?

CAMBRIDGE, Massachusetts — It is a theory that gives indigestion to mainstream archaeologists. Namely, that some of the immense blocks of the Great Pyramids of Egypt might have been cast from synthetic material – the world’s first concrete – not just carved whole from quarries and lugged into place by armies of toilers.

Such an innovation would have saved millions of man-hours of grunting and heaving in construction of the enigmatic edifices on the Giza Plateau.

“It could be they used less sweat and more smarts,” said Linn Hobbs, professor of materials science at the Massachusetts Institute of Technology.

“Maybe the ancient Egyptians didn’t just leave us mysterious monuments and mummies. Maybe they invented concrete 2,000 years before the Romans started using it in their structures.”

That is a notion that would dramatically change engineering history.

It has long been believed that the Romans were the first to employ structural concrete in a big way, although the technology may have come from the Greeks.

A handful of determined materials scientists are carrying out experiments with crushed limestone and natural binding chemicals – materials that would have been readily available to ancient Egyptians – designed to show that blocks on the upper reaches of the pyramids may have been cast in place from a slurry poured into wooden molds.

These researchers at labs in Cambridge, Philadelphia and St. Quentin, France, are trying to demonstrate that Egyptians of about 2,500 B.C. could have been the true inventors of the poured substance that is humanity’s most common building material.

At MIT, Hobbs and two colleagues teach a course called Materials in Human Experience. Over the years, undergraduates in the program have recreated from scratch such artifacts as samurai swords, tinkling Meso-American bells and even a swaying 60-foot, or 20-meter, plant-fiber suspension bridge like those built by the Incas.

Now a scale-model pyramid is rising in Hobbs’s sixth-floor lab, a construction made of quarried limestone as well as concrete-like blocks cast from crushed limestone sludge fortified with dollops of kaolinite clay, silica and natural desert salts – called natron – like those used by ancient Egyptians to mummify corpses.

The MIT pyramid will contain only about 280 blocks, compared with 2.3 million in the grandest of the Great Pyramids.

“The degree of hostility aimed at experimentation is disturbing,” he said. “Too many big egos and too many published works may be riding on the idea that every pyramid block was carved, not cast.”

Archaeologists, however, say there is simply no evidence that the pyramids are built of anything other than huge limestone blocks. Any synthetic material showing up in tests – as it has occasionally, even in work not trying to prove a concrete connection – is probably just slop from “modern” repairs done over the centuries, they say.

The idea that some pyramid blocks were cast of concrete-like material was aggressively advanced in the 1980s by the French chemical engineer Joseph Davidovits, who argued that the Giza builders had pulverized soft limestone and mixed it with water, hardening the material with natural binders that the Egyptians are known to have used for their famous blue-glaze ornamental statues.

Such blocks, Davidovits said, would have been poured in place by workers hustling sacks of wet cement up the pyramids – a decidedly less spectacular image than the ones popularized by Hollywood epics like “The Ten Commandments,” with thousands of near-naked toilers straining with ropes and rollers to move mammoth carved stones.”

Os dejo con una crucigrama que teneis que completar con las palabras que aparcen en negreta en el texto (en su forma de infinitivo, si se trata de un verbo, o singular, si se trata de un sustantivo). Teneis definiciones para ayudaros a identificar las palabras.

¿Tienes dudas sobre el funcionamiento del ejercicio?



  1. tec. 94 dice:


Deja tu comentario


Normas de uso de los comentarios: Este es un espacio de libre expresión para plantear preguntas u ofrecer puntos de vista o explicaciones, pero no todo vale. Se borrarán todos aquellos comentarios que consideremos insultantes o denigrantes. También se borrarán aquellos comentarios que no tengan ninguna relación con el tema.

volver arriba