2015-07-21
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to be filled … sth. to be open … sth. to move … and … of sth. to cut … sth. to pass … sth. to beep sth … sth. to be known … sth. to consist … sth. to be located … sth. to provide sth … smb.
VI. Translate the passage and answer the question: What was done to facilitate the setting of a foundation.
The Romans surmounted the problem of building bridge foundation in water by using cofferdams, which were temporary enclosures made of timber that were driven into the river bottom, made watertight with clay and then pumped dry to facilitate the setting of a foundation. This method was long used and only significantly improved with the development of the pneumatic caisson in the 19-th and 20-th centuries. In the early days of caisson use there were many casualties among workers who made a rapid transition from the compressed chamber to normal atmospheric pressure and developed caisson disease.
VII. Make the precis of the text
