Book excerpt: Where do Mark McGwire and Sammy Sosa's 1998 seasons rank in comparison with the greatest performers of all-time? When McGwire hit his 70th homerun in 1998 the baseball world went nuts. He shattered a record that had stood since 1961 when Roger Maris of the New York Yankees hit 61 HR's to break Babe Ruth's record of 60 that stood since 1927. Sosa chased McGwire during the season and finished his campaign with 66 homeruns, which would have broken the record. Would someone from the 1999 season mount an assault on the record books? The arguments and discussions as to who is the greatest player past and present will go on forever. Comparisons have been made Willie Mays vs. Hank Aaron, Joe Dimaggio vs. Ted Williams, Ty Cobb vs. Babe Ruth and today, Barry Bonds vs. Ken Griffey, Jr. Who's better? Are the players today better than their counterparts of the 20's, 30's, 50's or even the 70's? How do you compare one era with another? Today, equipment is much better and ballparks and the conditions are better. Motivational factors couldn't be any more different. For the most part the 'old-time' ballplayers played for the love of the game first. Yes, throughout history there have been salary squ