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
2009-06-24
7
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 mouth. 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" which 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 there 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 the crushing of the body, caused by a sudden diving into deep water. The sudden rise to the surface could kill the 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 that the diver could be given a constant supply of air. The diver could then move around under the ocean without worrying about the air supply.
During the 1940s diving underwater without a special suit became popular. Instead, divers used a breathing 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 the 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 underneath them. A special rubber suit enabled them to stay in cold water for long periods, collecting specimens of animal and vegetable life that 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 "scuba".
Invented by two Frenchmen, Jacques Cousteau and Emile Gagnan, the scuba consists of a mouth-piece joined to one or two tanks of compressed air which are attached to the 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 the wonders of the sea.
选项
A、an Italian professor invented a large air bag.
B、men invented the best diving devices.
C、an Italian painter designed a complete diving suit.
D、an air bag.
答案
C
解析
文章第一段提到"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"。
转载请注明原文地址:https://kaotiyun.com/show/YTTd777K
本试题收录于:
公共英语五级笔试题库公共英语(PETS)分类
0
公共英语五级笔试
公共英语(PETS)
相关试题推荐
TheAmericanFamilyIntheAmericanfamilythehusbandandwifeusuallyshareimportantdecisionmaking.Whenthechildrenareo
TheAmericanFamilyIntheAmericanfamilythehusbandandwifeusuallyshareimportantdecisionmaking.Whenthechildrenareo
TheAmericanFamilyIntheAmericanfamilythehusbandandwifeusuallyshareimportantdecisionmaking.Whenthechildrenareo
APopularityofScienceFictionBAFairlyNewDevelopmentCClassicsofScienceFictionDDifficultyinKeepingaheadofSc
APopularityofScienceFictionBAFairlyNewDevelopmentCClassicsofScienceFictionDDifficultyinKeepingaheadofSc
RecentstudiesbytheCouncilofEuropehaveindicatedthatThelastsentenceinthesecondparagraphimpliesthat
SpaceResearchDoeswalkingonthemoonmakelifebetterforpeopleonearth?【51】alltheproblemsofourownworld,whyshou
SpaceResearchDoeswalkingonthemoonmakelifebetterforpeopleonearth?【51】alltheproblemsofourownworld,whyshou
ImproveComputer-researchSkillsLikemanycollegestudents,JoseJuarezcarriesaroundapocket-sizedcomputerthatletshi
Howmuchwouldfourpoundsofteaweighifitwastaken4,000milesoutfromthesurfaceoftheearth?Wedonotfeelthegravi
随机试题
某教师在进行“探问生命”课程导入时,通过播放自制视频“生命的春天”引导学生感受生命的多种多样、多姿多彩。这是运用课堂导入中的()。
来自心脏的静脉
A.“4”字试验阳性B.伸肌腱牵拉试验(Mills征)阳性C.杜加(Dugas)征阳性D.直腿抬高试验(Lasegue)阳性E.压头试验阳性肱骨外上髁炎主要体征为
锅炉炉墙由三层平壁组成,内层是耐火砖层,外层是红砖层,中间石棉保温层。由内到外三层的厚度和热导率分别是:δ1=0.23m,λ1=1.20W/(m.K),δ2=0.05m,λ2=0.095W/(m.K),δ3=0.24m,λ3=0.60W/(m.K)。炉墙内
《水土保持法》规定,为防止水土流失,生产建设活动结束后,其取土场、开挖面和废弃的砂、石、土存放地的裸露土地,必须()。
下列四项工作内容哪项不属于行政执行的实施阶段?()
以下哪些法律可以作为我国基层群众自治的法律依据和法律保障()
Systemanalysisistraditionallydonetop-downusingstructuredanalysisbasedon(71).Object-orientedanalysisfocusesoncr
请编制程序,其功能是:内存中连续存放着16个二进制字节数,在原16个数的第4和第5个数之间插入00H,在原16个数的第8和第9个数之间插入55H,在原16个数的第12和第13个数之间插入AAH,在原16个数的最后加入FFH。将按上述方法插入4个字节数后得到
Lookatthenotesbelow.Youwillhearatelephonetalkingaboutclaims.TelephoneMessageCaller’sname
最新回复
(
0
)