I just happened upon a wonderful blog that I hadn't seen before: Up and Down California. The blog is, one post at a time, publishing and illustrating the travels of the 1860 Whitney Survey of California.
Although, like most blogs, the website loads with the newest article at the top, the authors have kindly provided an index and you can start reading from the beginning by going here.
This is great work, and the pictures really bring the stories to life. Enjoy!