Early Geological map of the state of New Jersey.
During the 19th Century, at various times, the State of New Jersey retained a State Geologist. After a lapse of 3 years from 1861 to 1864, "An act to complete the Geological Survey of the State" 12 passed on March 30, 1864. George Hammell Cook 1818–1889) was given the post and the charge.
A former civil engineer and Rutgers professor, he had been Kitchell's assistant geologist during the survey years of the 1850s. In 1864, Cook also became vice president of Rutgers College; he had been instrumental in the institution's quest for land-grant status. (Rutgers's Cook College, today's School of Environmental and Biological Sciences, was named for him.)
Four years later, as required by the 1864 act, Cook produced large-scale geological maps of the state to accompany his report.