 The 1880s proved disastrous for Cope . Marsh 's close association with the Geological Survey gave him the resources to employ 54 staff members over the course of ten years . His teaching position at Yale meant he had guaranteed access to the American Journal of Science for publication . Cope had his interest in the Naturalist , but it drained him of funds . After Hayden was removed from the survey , Cope lost his source of government funding . His fortune was not enough to support his rivalry , so Cope invested in mining . Most of his properties were silver mines in New Mexico ; one mine yielded an ore vein worth $ 3 million in silver chloride . Cope visited the mines each summer from 1881 to 1885 , taking the opportunity to supervise or collect other minerals . For a while he made good money , but the mines stopped producing and by 1886 he had to give up his now @-@ worthless stocks . The same year he received a teaching position at the University of Pennsylvania . He continued to travel west , but realized he would not be able to best Marsh in cornering the market for bones ; he had to release the collectors he had hired and sell his collections . During this period , he published 40 to 75 papers each year . With the failure of his mines , Cope began searching for a job , but was turned down at the Smithsonian and American Museum of Natural History . He turned to giving lectures for hire and writing magazine articles . Each year , he lobbied Congress for an appropriation with which to finish his work on " Cope 's Bible " , a volume on Tertiary vertebrates , but was continually turned down . Rather than work with Powell and the survey , Cope tried to inflame sentiment against them . 
