Scientists are restoring the map of ancient Rome

　　Since the fall of the Roman Empire,the Forma Urbis Romae-an ancient map detailing every room, staircase(室内 楼梯) and portico(有圆柱的门廊) of Rome in the third centure A. D.-has lain in thousands of scattered pieces. But now, Stanford University scientists are hoping some innovati ve computer work will put many of the pieces back toget her again.

　　A closeup of one fragment of the Roman census(人口调查) map: lines represent walls, the two samll V's visible a re staircases, and the five round dots just below top c enter indicate a portico supported by columns. The scal e is roughly 214:1. The map, originally measuring 18.2 by 13.7 meters (60 by 45 feet), once graced the back wa ll of Rome's census bureau. But over the centuries, man y of its marble slabs(大理石板) were scavenged(挑捡) to build other structures. Eventually the wall collapsed, leavin g the remainning pieces protected under the rabble. Tho se pieces are now in Rome's Museum of Roman Civilizatio n.

　　Last year, researchers digitally scanned every surf ace of all 1,163 surviving map fragments into their com puters. A three- dimensional model is being built of ea ch piece, and all the pieces will then be fitted back t ogether with a unique computer program.

　　The goal, says James Edward Davis of Stanford, is t o narrow the possible configurations(轮廓) from millions to a manageable number. Then someone at the museum in R ome can see if they really do it .

　　"When you hold two of these fragements together,"Da vis says, "you can feel whether or not they fit togethe r. The fragments slide across each other until they are just right,and then they feel as if they stick."

　　While the existing pieces constitute only 15 percen t of the original map, researchers feel many of them ar e from a single part of the city- the area around the i mperial forums, Coliseum, and Palatine Hill- and should , therefore, fit together.