Historian Bill Watson holds the tooth remains of one of the Irish train workers found in Duffy's Cut in his office at Immaculata College in Malvern, Pennsylvania on March 8, 2014. REUTERS/Mark Makela... more 
Historian Bill Watson holds the tooth remains of one of the Irish train workers found in Duffy's Cut in his office at Immaculata College in Malvern, Pennsylvania on March 8, 2014. REUTERS/Mark Makela less 
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Reuters | Photo By MARK MAKELA / Reuters
Mon, Mar 10, 2014 7:14 AM EDT