Noah Brooks 
First Across the Continent / The Story of the Exploring Expedition of Lewis and Clark in 1804-5-6 [PDF ebook] 

The writer relies heavily on Lewis and Clark’s journals, using their own words to convey their experiences. 
The accounts are vivid. You can almost experience first hand the exciting adventure. You almost feel as if you were with them on this amazing expedition. The details are fascinating. Their encounters with the bears are so well written that you will want to join in with them in seeking a safe place to escape for fear of your life.
Soome periods of food shortage and a lot of dog eating on the way. Also gives a great insight into the lives of the many unknown native American tribes that have become extinct in the intervening years since 1804. Join them as they meet the different tribes of Indians and wildlife in this new found land. This book describes their day by day struggles as they make their way up the Missouri, over the mountains and on to the Pacific.