Nuttall became the most traveled naturalist of his generation, six expeditions as far as Hawaii. Most collection (for plants and animals) trips were done alone and on foot much like John James Audubon. He was humble; he admitted to getting lost and rescued by other travelers in his journals. Some folks of that time described him as a "whimsical kind of madman". Could be, Nuttall was singularly focused on collecting plants and animals and information about them. His hard work paid off when he got lecturer position at Harvard University in 1823. He authored, published an affordable bird guide A Manual to the Ornithology of the United States and Canada in 1833. He also coauthored Flora of North America with John Torrey and Asa Gray.
He is memorialized with three bird species named after him (can you name them?). Numerous plants are also bear his name. I found two yesterday along the Clark Fork River in Missoula, MT: Nuttall's Rockcress (Arabis nuttallii) and Nuttall's Violet (Viola nuttallii). Could not find Nuttall's Pussytoes in bloom for three of a kind :-) What's in your neighborhood that may have been discovered 150 years ago?
Reference: Audubon to Xantus The Lives of Those Commemorated in North American Bird Names, Barbara and Richard Mearns, 1992, Academic Press Limited, San Diego, CA