Internet Archive has the three main volumes of Edward Robinson’s Biblical Researches in Palestine (Boston: Crocker and Brewster). The volumes record observations from Robinson’s mid-19th century travels in Palestine with Eli Smith and others. On Internet Archive, the volumes are included on the same page with several others, and the labeling is somewhat unclear. The direct links for the Biblical Researches files are, however, as follows: vol. 1, vol. 2, and vol. 3.