Holmessaid，"Somebodysentaletterwithfivepips（桔核）initfromIndia，andarrivedsevenweekslatertokillJohn'suncle．ThentheysentfivepipsfromScotlandandarrivedthreedayslatertokillJohn'sfather．Nowtheyhaves

　　Holmes said，"Somebody sent a letter with five pips （桔核） in it from India，and arrived seven weeks later to kill John's uncle．Then they sent five pips from Scotland and arrived three days later to kill John's father．Now they have sent five pips to John from London!"

　　"The letters are all from sea ports （海港）．The writer was on a ship when he wrote the letters，"I replied．

　　"Very good，Watson!And John's enemy is in London already!"

　　"Well，I hope they won't kill young John，"I said．

　　But they did．The next morning，we read in the newspaper that a policeman found him die near Waterloo station．Holmes was very angry about it．

　　"He came to me for help and those men murdered him!I'm going to find them，if it's the last thing I do!"he said to me，and he hurried out of the house．

　　At night，when he came back，he was tired，but pleased，he said，"I know the names of John's enemies!And now I'm going to send them a surprise!This will frighten them!"He took five pips from an orange and put them in an envelope （信封）．On it he wrote"S．H．forJ．C．"

　　"I'm sending the pips to captain James Calhoun．His ship is called the Star．He and his men are sailing back to Georgia，USA．"

　　"How did you find him，Holmes？"I asked．

　　"Ship's papers，"he said，"I've looked at hundreds of them today．Only one ship，the Star，was in the three ports at the right times，this morning the Star left London to sail back to Georgia．I found out that the captain and two of his men，all Americans，weren't on the ship last night，so I'm sure they killed John．When they arrive in America，they'll get the pips and then the police will catch them!"

　　56．This story may be taken from___．

　　A．a science fiction B．a history book

　　C．a detective novel D．a travel guide

　　57．Holmes was___ about John's death．

　　A．curious B．angry