The E102 is a strange card set. It consists of twenty-five players, three of which have picture variations (Doyle, Miller and Wagner). One additional card has a picture variation and a wrong name (Schmidt).
Those are pretty typical for an issue of this era. What makes this a strange set is that no one is certain about where these came from originally. There is no particular candy company associated with this set. There is no company identification on either side of the card.
Another problem with this set is that no one can agree 100% on when it was issued. I imagine that would clear up if a company is ever identified as the manufacturer. Until then, there are several years which this set is listed. I've seen listings as early as 1908 and as late as 1911, but the general consensus is that this set was issued in 1910. According to the American Card Catalog compiled by Jefferson Burdick, these cards were issued between 1909 and 1911 by a anonymous caramel company.
The White Sox have one card in this twenty-five card set.
This set is also a bit of an anomaly, since the player's position is listed. In the case of Dougherty, left field is specifically listed. Typically, the player's position is not mentioned on the front of a card in this era. In the instances that they are, usually the more generic position of outfield would be given to a left fielder.
The card front is bright and the colors pop, which is the norm for cards from this era. The E102 cards are especially condition sensitive. Finding one in pristine condition is almost an impossible task. If you can find one, in any condition, cherish it.