like so many stone buildings that had been well-designed , it succeeded in confounding the closely observing eye with contradictions : its stone solidity was somehow balanced by the delicacy of its arches and slim columns ; it looked both bank-safe squat and yet slim and clean ( well , it was slim as city buildings went , especially those erected around the turn of the century , and the windows , crisscrossed with narrow strips of iron , were graceful and rounded ) .