The Copts are the result of crossbreeding with all the nations that successfully dominated Egypt. It is wrong to seek in them the principal features of the old race." Also in 1839, Champollion's and Volney's claims were disputed by Jacques Joseph Champollion-Figeac, who blamed the ancients for spreading a false impression of a Negro Egypt, stating "The opinion that the ancient population of Egypt belonged to the Negro African race, is an error long accepted as the truth. ... Volney's conclusion as to the Negro origin of the ancient Egyptian civilization is evidently forced and inadmissible." The debate over the race of the ancient Egyptians intensified during the 19th century movement to abolish slavery in the United States, as arguments relating to the justifications for slavery increasingly asserted the historical, mental and physical inferiority of black people. For example, in 1851, John Campbell directly challenged the claims by Champollion and others regarding the evidence for a black Egypt, asserting "There is one great difficulty, and to my mind an insurmountable one, which is that the advocates of the negro civilization of Egypt do not attempt to account for, how this civilization was lost... Egypt progressed, and why, because it was Caucasian." The arguments regarding the race of the Egyptians became more explicitly tied to the debate over slavery in the United States as the United States escalated towards civil war. In 1854, Josiah C. Nott with George Glidden set out to prove: "that the Caucasian or white, and the Negro races were distinct at a very remote date, and "that the Egyptians were Caucasians."" Samuel George Morton, a physician and professor of anatomy, concluded that although "Negroes were numerous in Egypt, but their social position in ancient times was the same that it now is [in the United States], that of servants and slaves." In the early 20th century, Flinders Petrie, a Professor of Egyptology at the University of London, in turn spoke of a Nubian queen, Aohmes Nefertari, who was the "divine ancestress of the XVIIIth dynasty". He described her physically as having "had an aquiline nose, long and thin, and was of a type not in the least prognathous". Egypt was not a popular civilization with all African Americans at the time, because they often associated Egypt with slavery. Black spirituals such as Go Down Moses related the slavery of blacks in America to the bondage of the Israelites in Egypt.