Gold dust, gold bars, gold coins, legal papers, checks and drafts traveled in the famous green treasure boxes with the Wells Fargo Bags full of bounty, stored under the stagecoach driver's seat. Loaded with bullion, they could weigh from 100 to 150 lbs. "About as much as one likes to shoulder to and from the stages," wrote John Q. Jackson, Wells Fargo agent, in an 1854 letter to his father. Because they carried the most valuable assets of the West, these sturdy boxes of Ponderosa pine, oak, and iron were more prized by highway bandits than anything else.

But the real security of the treasure boxes came from who was guarding them--the Wells Fargo shotgun messengers. They were "the kind of men you can depend on if you get into a fix," according to Wells Fargo detective Jim Hume. If thieves were foolhardy enough to try and steal a treasure box in transit, they would find themselves staring down the barrel of a sawed-off shotgun, loaded with 00 buckshot, and possibly held by Wyatt Earp himself.

Despite these efforts, there was a masked highwayman who managed to rob 27 stagecoaches--the infamous Black Bart. Wells Fargo detectives eventually caught up with him. He served his four years in San Quentin and then disappeared forever.