The University of Cambrige, England, divides the different kinds of honours bachelor's degree by Tripos, a word which has an obscure etymology, but which may be traced to the three-legged stool candidates once used to sit on when taking oral examinations. A common (but untrue) myth says that students used to receive one leg of a stool in each of their three years of exams, receiving the whole stool at graduation. An undergraduate studying mathematics is thus said to be reading for the Mathematical Tripos, whilst a student of English is reading for the English Tripos. (In most traditional English universities a student is expected to register study one field exclusively rather than having 'majors' or 'minors' as in American universities. In practice however, English degree fields may be fairly interdisciplinary in nature, depending on the subject. The multi-part Tripos system at Cambridge also allows substantial changes in field between parts, and the Natural Sciences Tripos is especially designed to allow a highly flexible curriculum across the sciences).