A Century of Galaxy Spectroscopy

The first successful spectrum of M31, published by Scheiner in 1899, showed the object to be a system of stars like the sun. Since then, spectroscopy has played the major role in discovering characteristics of galaxies and their relation to the large scale universe. For astronomers, the 20th century is truly the centuryof galaxy studies. Following a brief historical introduction, I will concentrate on several themes of contemporary extragalactic spectroscopy: internal kinematics as a means to determine the mass density of the universe, peculiar motions in order to study large-scale mass distributions in the universe, and details of galaxy kinematics which offer evidence that gravitational interactions and mergers are a driving force in galaxy evolution. I will conclude with several outrageous predictions for the next century, too radical to commit to paper.