Waves can also be separated into transverse and longitudinal waves. In a transverse wave, the motion of the particles of the medium is at right angles (i.e., transverse) to the direction the wave moves.
The experiment's name comes from the Tuskegee Institute, the black university founded by Booker T. Washington. Its affiliated hospital lent the PHS its medical facilities for the study, and other predominantly black institutions as well as local black doctors also participated.
In 1895, Du Bois became the first African American to receive a Ph.D. in the subject of history from Harvard University. He then studied in Germany but ran out of funds before he could earn a post-doctoral degree.