Montgomery Block, or "Monkey Block," was the tallest building east of Chicago in 1862. Legions of Chinese workers helped build the foundation. The sandy base was stacked with redwood tree trunks and abandoned Gold Rush ships from then Yerba Buena Cove. It was the first fireproofed office structure with deep set windows, iron girdles, stone firewalls. Lawyers, jazz musicians, writers including Mark Twain, passed through it. The building survived the 1906 fire, but not the 1956 demolition. Today, it's the Transamerica building. The redwood grove behind is the only reminder of its past, beneath.