Pony riders faced endless dangers and difficulties as they worked for the Pony Express. They galloped across terrain that was slippery mud in winter and choking dust in summer, alive with flies and mosquitoes, home to wild animals and hostile Native American tribes. They forded treacherous rivers and struggled over rugged snow-covered mountains.

Traveling at night with only the moon and the stars to light their path, they had to maintain a sharp lookout and rely on the instincts of their horses to keep them on the trail. Some men were thrown off and broke bones. Some were wounded. Some rode when they were sick. Those who coped with illness and injury did so miles from the nearest doctor and had to rely on the crude first aid skills of the station keeper to keep them in the saddle.

At...