A horse tale with a different twist; One Horse/One Hundred Miles/One Day, by Sam Savitt. New York: Dodd, Mead, & Co.

The Tevis Cup Endurance Ride grew out of an argument in 1955 about whether the horses of the 1850 Pony Express days were better than the horses of today. A decision was made to find out by holding a 100-mile ride in 24 hours, using a trail once traveled by Wells Fargo Express riders that stretches from Squaw Valley to Auburn, Calif.

This challenging trail covers a wide range of mountainous terrain, varying between elevations of 4,000 and 8,000 feet in some places, with sheer drops that sometimes have to be negotiated on foot that sometimes have to be negotiated on foot holding onto a horse's tail. It's no wonder that the annual event is considered to be the most demanding endurance ride in the United States, with hundreds of riders aspiring to qualify for it each year.

It's no wonder, either, that Sam Savitt, a well-known author and illustrator of a variety of books about horses, was captivated. After observing this "Olympic level" competition, he says he learned a new meaning of the word "endurance." Savitt not only describes a Tevis Cup Ride from beginning to end, in words and sketches, but also weaves in colorful historical material about the Pony Express riders.

The book follows the riders of two participants: Richard Barsaleau, a veteran competitor, who trained a young thoroughbred for a first-time entry, and first-time competitor Kathy Tellington, who trained an experienced Arabian horse lent by a friend.

It all adds up to a grueling 100 miles in one day -- and positive proof that today's horses are more than equal to those of the Pony Express.