Contains one leather bound journal (80 p.) of an Army surgeon assigned to Captain William H. Warner's expedition to the Sierra Nevada. Entries were recorded in two parts. The first part was recorded at the time Hewit was actually with the expedition and covers the period, August 1 to September 3, 1849. It contains dated entries with observations on illnesses, California Indians, including their diet and enslavement by white settlers, Captain John Sutter, gold mining, bears digging up graves, emigrant trains, and his own long recuperation in Hawaii from a lingering illness. He resumes the second part of the journal on March 16, 1850 while recuperating in Hawaii by recalling the rest of the events in the expedition while he was with it. He gives numerous details of being ill and notes that a rumor of Warner's death was confirmed on Oct. 6, 1849. The journal also contains 9 pages of surgery notes, dated 1845(?), concerning wounds to the head and tongue, and neuralgia.