I'm with John Dreker and SABRs 19th century committee, but for slightly different reasons than John writes about. In short, Deacon was the best catcher in the game during the 1870s, an era in which the catcher was considered the most important position in baseball. Team success relied on having a quality catcher more so than any other position including pitcher. The danger level was truly off the charts in 1870 with Deacon moving up to behind the batter when runners were on base (a tactic credited to Deacon) with virtually no protective gear, and dealing with increasingly fast pitch speeds (fast enough for effective curve balls etc.). To add to his catching skills, Deacon was feared at bat, either leading or among the leaders with frequency (BA, RBIs, etc.). Deacon was the gold standard during the 1870s, the stuff of legend, but his position did take a toll and he had to re-invent himself for the 2nd half of his career, moving to 3rd base. In his later years, all the way up to the end when he was the oldest player in baseball, he posted respectable numbers. Bill James even rated him as top 100 3rd basemen (76th). Unfortunately, I believe he was best remembered for his less impressive performance from 1880-1890 as opposed to his superstar status from the late 1860s-1879.
For more info on Deacon including display of
all 9 poses in the Old Judge set, visit this older link:
http://www.net54baseball.com/showthread.php?t=126514