Exercise to Prepare TOEFL Test in Reading

READING I

This question has often been posed: why were the wright brothers able to succeed in an effort at which so many others had failed? Many explanations have been mentioned , but three reasons are most aften cited. First, they were a team. Both men worked congenially and cooperatively, read the same books, located and shared information, talked incessantly about the possibility of manned flight, and served as aconsistent source of inspiration and encouragement to each other. Quite simply, two geniuses are better then one.

Both were glider pilots. Unlike some other engineers who experimented with the theories of flight, orville and wilbur wright experienced the practical aspects of aerodynamics by building and flying in kites and gliders. Each craft they built was slightly superior to the last, as they incorporated  knowledge that they had gained from previous failures. They had realized from their experiments that the most serious challenge in manned flight would be stabilizing and maneuvering the aircraft once it was airborne. While others concentrated their efforts on the problem ot achieving lift for take-off, the wright brothers were focusing on developing a three-axis control for guiding their aircraft. By the time that the brothers started to build an airplane, they were already among the world’s best glider pilots; they knew the problems of riding the air first hand.

READING II

In addition, the wright brothers had designed more affective wigs tor the aiplane thand had been previously engineered. Using a wind tunnel, they tested more than two hundred different wing designs, recording the effects of slight variations in shape on the pressure of air on the wings. The data from these  experiments allowed the wright brothers to construct a superior wing for their aircraft.

In spite of these advantages, however, the wright brothers might not have succeeded had they not been born at precisely the opportune moment in history. Attempts to achieve manned flight in the early nineteenth century were doomed because the steam engines that powered the aircrafts were too heavy in proportion to the power that they   produced. But by the end of the nineteenth century, when the brothers were experimenting with engineering options, a relatively light internal combustion engine had already been invented, and they were able to bring the ratio of weight to power with in accetable limits for flight. 

READING III

            Although its purpose and techniques were often magical, alchemy was, in many ways, the predecessor of the modern science of chemistry. The fundamental premise of alchemy derived from the best philosophical dogma and scientific practice of the time, and the majority of educated persons between 1400 and 1600 believed that alchemy had great merit.

            The earliest authentic works on European alchemy are those of the english monk Roger Bacon and the German Philosopher St. Albertus Magnus. In their treatises they maintained that gold was the perfect metal and that inferior metals such as lead and mercury were removed by various degrees of imperfection from gold. They further asserted that these base metals could be transmuted to gold by blending them with a substance more perfect than gold. This clusive substance was referred to as the philosopher’s stone. The process was called transmutation.

            Most of the eraly alchemists were artisans who were accustomed to keeping trade secrets and often resorted to cryptic terminology to record the progress of their work. The term sun was used for gold, moon for silver, and the five known planets for base metals.

READING IV

The keystone arch was used by almost every early civilization. To build a keystone arch. Stones are cut so that the opposite sides taper toward each other slightly. The upper and lower surfaces are caved so that when several stones are placed side by side, the upper and lower surfaces meet in smooth, continuous cures. Some from of scaffolding is built under the arch and shaped to accept the curved underside of the stones. Then the stones are fitted in place one by one. The keystones is the top center stone, the lust to be dropped into position. Afterwards, the scaffoldingis removed and the arch is self-supporting.