Book excerpt:  Inside Madison Square Garden, the City Ring was the altar of pugilism from 1925 until 2007. Hosting countless championship fights, historic main events and memorable undercards, it was center stage of boxing history. The ring now rests at the International Boxing Hall of Fame in Canastota, New York--its 132 assembled pieces memorializing a key facet of 20th century American life. While many books have been written about great fistic contests that took place at Madison Square Garden, this is the first to focus on its Holy Grail.