C
Reading about history is nice, but finding ties to long-ago historical s in your own backyard is really exciting．
In their heavily populated area, neighbors Adam Giles,13, and Derek Hann．12, uncovered pieces of glass that looked quite different from what’s used today．“After digging about two feet down, I came across an interesting bottle,” Derek said．The bottle had a “pontil scar” on the bottle, an indication that it was hand-blown rather than machine made．It also had the name “Fraser” on one side．
Adam found remains of a green bottle and some very thick brown glass—again, far different from today’s．
After doing research on the computer, the boys contacted Aimee Wells of the county’s Cultural Resources office．She showed them a computer program that digitally puts old maps over modern satellite photographs．
Bingo! Their back yards were once part of a military（军事的） encampment（营地） called Camp Alger used by Ohio soldiers on their way to fight in the Spanish-American War in 1898．
So how do a few bottles get connected to a brief war that was more than a century ago? “We get there by good judgment,” Wells said．“We know the time period of the bottles and what happened in that area．” Anyone can dig a hole, but archaeologists seek a deeper understanding．How do objects found relate to things around them?
When Derek and Adam realized that a solider might have held that Fraser bottle 110 years ago, they wondered what he might have been thinking．What did he see as he looked around him? How did he pass the time waiting to go into battle?
Historical records show that while waiting for orders, the soldiers in and around Camp Alger played baseball, played instruments and walked seven miles to the Potomac River once a week for baths．A spread of strange fever forced the closing of the camp, and there are no buildings to study．“What’s left is only what’s in the ground,” said Wells．
Derek’s and Adam’s back yards have joined the 3,400 places listed on the county’s register of archaeological sites．The boys were given tips on how to dig effectively and safely, and on how to document the location of items found．
The official record of their finds serves as another piece of the puzzle for historians seeking to form a more complete story of what happened．
“Not everyone is going to have historical objects in their own yard,” Wells said．“That’s okay．Make your own time capsule and bury it．What would you want people to know about your life years from now?”
63．What is the passage mainly about?
A．How Adam Giles and Derek Hann dug out the remains of an ancient military encampment．

B.What Adam Giles and Derek Hann found in their back yard and its relationship with an encampment．

C.The great contribution Adam Giles and Derek Hann made to the cause of archaeology．

D.The tips on how to dig out ancient objects buried under the ground safely and effectively．
．From the passage, we can see that the boy’s discovery _______．
A．includes all kinds of hand-made and machine- made glass．