首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Until men invented ways of staying underwater for more than a few minutes, the wonders of the world below the surface of the sea
Until men invented ways of staying underwater for more than a few minutes, the wonders of the world below the surface of the sea
admin
2015-01-26
53
问题
Until men invented ways of staying underwater for more than a few minutes, the wonders of the world below the surface of the sea were almost unknown. The main problem, of course, lies in air. How could air be supplied to swimmers below the surface of the sea? Pictures made about 2, 900 years ago in Asia show men swimming under the surface with air bags tied to their bodies. A pipe from the bag carried air into the swimmer’s mourn. But little progress was achieved in the invention of diving devices until about 1490, when the famous Italian painter, Leonardo da Vinci, designed a complete diving suit.
In 1680, an Italian professor invented a large air bag with a glass window to be worn over the diver’s head. To "clean" the air a breathing pipe went from the air bag, through another bag to remove moisture, and then again to the large air bag. The plan did not work, but it gave later inventors the idea of moving air around in diving devices.
In 1819, a German, Augustus Siebe, developed a way of forcing air into the head-covering by a machine operated above the water. Finally, in 1837, he invented the " hard-hat suit" was to be used for nearly a century. It had a metal covering for the head and an air pipe attached to a machine above the water. It also had small openings to remove unwanted air. But mere were two dangers to the diver inside the " hard-hat suit". One was the sudden rise to the surface, caused by a too great supply of air. The other was me crushing of the body, caused by a sudden diving into deep water. The sudden rise to the surface could kill me diver; a sudden dive could force his body up into the helmet, which could also result in death.
Gradually the "hard-hat suit" was improved so mat the diver could be given a constant supply of air. The diver could men move around under me ocean without worrying about the air supply.
During the 1940s diving underwater without a special suit became popular. Instead, divers used a breaming device and a small covering made of rubber and glass over parts of the face. To improve the swimmer’s speed another new invention was used: a piece of rubber shaped like a giant foot, which was attached to each of me diver’s own feet. The manufacture of rubber breathing pipes made it possible for divers to float on the surface of the water, observing the marine life underneam them. A special rubber suit enabled them to stay in cold water for long periods, collecting specimens of animal and vegetable life mat had never been obtained in the past.
The most important advance, however, was the invention of a self-contained underwater breathing apparatus, which is called a " sucba".
Invented by two Frenchmen, Jacques Cousteau and Emile Gagnan, the scuba consists of a mouthpiece joined to one or two tanks of compressed air which are attached to me diver’s back.
The scuba makes it possible for a diver-scientist to work 200 feet underwater or even deeper for several hours. As a result, scientists can now move around freely at great depths, learning about me wonders of the sea.
Siebes’ invention was not a perfect one, because
选项
A、too small a supply of air could result in a sudden rise to the surface.
B、a sudden dive into deep water could cause the crushing of the body.
C、the air pipe attached to a machine could be above the surface.
D、both A and B
答案
B
解析
事实细节题。信息定位在文章第三段最后三句。其中提及two dangers。One was the…the otherwas the…,A选项中提及too small supply与文中too great supply意义截然相反。选项B与文章原意相符。由此可知,答案为B。
转载请注明原文地址:https://kaotiyun.com/show/URLO777K
0
考博英语
相关试题推荐
Tosurviveintheintensetradecompetitionbetweencountries,wemust______thequalitiesandvarietiesofproductswemaketo
Eventhoughwehadbeentoherhouseseveraltimesbefore,westilldidnotremember______.
Oneofthebasiccharacteristicsofcapitalismistheprivateownershipofthemajormeansofproduction—capital.Theownership
Today,theTowerofLondonisoneofthemostpopulartourist【1】andattractso-verthreemillionvisitorsayear.Itwasoccasio
Themedia’s______inthepresident’sprivatelifeswitchedtheattentionawayfromtherealissues.
ThemanwhoinventedCoca-ColawasnotanativeAtlantan,butonthedayofhisfuneraleverydrugstoreintowntestimoniallysh
Forsomeonewhoselifehasbeenshattered,HiroshiShimizuisremarkablycalm.InacrampedTokyolawoffice,thesubdued,bitte
(中国矿业大学2006年试题)Generally,acomputerisanydevicethatcanperformnumericalcalculations.Currently,【1】,thetermusually
(中国矿业大学2006年试题)Generally,acomputerisanydevicethatcanperformnumericalcalculations.Currently,【1】,thetermusually
Engineeringstudentsaresupposedtobeexamplesofpracticalityandrationality,butwhenitcomestomycollegeeducationIam
随机试题
一项经纪业务的最终完成,其作用的最终是()。
会计电算化的近期计划应与中长期计划相适应。 ( )
下列表述有误的是()。
普通附息债券的凸性()。
下列选项中属于我国证券登记结算机构业务范围和职能的有()。Ⅰ.接受上市申请,安排证券上市Ⅱ.证券的存管和过户Ⅲ.证券持有人名册登记Ⅳ.受发行人的委托派发证券权益
丁墨在他的小说《他来了,请闭眼》中,塑造了高智商、严谨和善于推理的犯罪心理学家薄靳言的形象,这属于()。
在我国远古社会的传说中,相传()品尝百草,救民疾苦,发明了原始医药;“耕而作陶”,发明了原始制陶业;教人耕种,出现了原始农业和原始文化
如果你是老师,该怎样激发学生的学习动机?
半殖民地半封建中国的资产阶级分为大资产阶级和小资产阶级两部分。
AHealthProfileAhealthprofileisaportraitofallofthefactorsthatinfluenceyourhealth.Todrawyourhealthprofil
最新回复
(
0
)