Chunks of this city's rich and eclectic architectural history tumble to the ground every few days, piece by piece, forever lost in the rubble. Neo-Baroque and Art Deco treasures deteriorate at an alarming rate. Every three days, there are two partial or total building collapses in Central Havana alone, according to architectural experts. No official figures are available. "Buildings are standing by sheer luck," said architect Jose Antonio Choy, president of a Cuban nonprofit organization devoted to the conservation of Havana's modern architecture. In September, after Hurricane Ike's lethal 41-hour odyssey across much of the island, authorities reported 67 buildings...