"All the works of the mound-builders of our country are exceedingly interesting to the antiquarian and are valuable as illustrating the habits, customs, and condition of the people by whom they were formed, but the sepulchral tumuli surpass all others in importance in this respect. Although usually simple in form and conveying thereby no indications of the characteristics of the people by whom they were erected, yet when explored they reveal to us, by their internal structure and contents, more in regard to the habits, beliefs, and art of their authors than can be learned from all their other works combined."

Cyrus Thomas (1825 – 1910) was a U.S. ethnologist and entomologist prominent in the late 19th century and noted for his studies of the natural history of the American West.