the start. Morton claimed that he could define the intellectual ability of a race by the skull capacity. A large volume meant a large brain and high intellectual capacity, and a small skull indicated a small brain and decreased intellectual capacity. He was reputed to hold the largest collection of skulls, on which he based his research. He claimed that each race had a separate origin, and that a descending order of intelligence could be discerned that placed Caucasians at the pinnacle and Negroes at the lowest point, with various other race groups in between. Morton had many skulls from ancient Egypt, and concluded that the ancient Egyptians were not African, but were Caucasian. His results were published in three volumes between 1839 and 1849: the Crania Americana, An Inquiry into the Distinctive Characteristics of the Aboriginal Race of America and Crania Aegyptiaca. Morton's skull collection was held at the Academy of Natural Sciences of Philadelphia until 1966, when it was transferred to the Penn Museum, where it is presently curated. Morton's theories were very popular in his day, and he was a highly respected physician and scientist. The anthropologist Aleš Hrdlička called Morton "the father of American physical anthropology". Crispin Bates has noted that Morton's "systematic justification" for the separation of races, along with the work of Louis Agassiz, was also used by those who favoured slavery in the United States, with the Charleston Medical Journal noting at his death that "We of the South should consider him as our benefactor for aiding most materially in giving to the negro his true position as an inferior race." Craniology Morton claimed in his Crania Americana that the Caucasians had the biggest brains, averaging 87 cubic inches (1,426 cc), Indians were in the middle with an average of 82 cubic inches (1,344 cc) and Negroes had the smallest brains with an average of 78 cubic inches (1,278 cc). Morton believed that the skulls of each race were so different that a wise creator from the beginning had created each race and positioned them in separate homelands to dwell in. Morton believed that cranial capacity determined intellectual ability, and he used his craniometric evidence in conjunction with his analysis of anthropological literature then available to argue in favor of a racial hierarchy which put Caucasians on the top rung and Africans on the bottom. His skull measurements (by volume) then came to