Edward William Morley graduated from Williams College in 1860 after three years of undergraduate work and one of research in the observatory. Home-schooled by his parents, Williams alumnus Sardis B. Morley and Anna Morley, Edward entered college as a sophomore at 19. He was expected to follow in his father’s footsteps and become a minister. After a few years of seminary school and a brief time serving his country in the Civil War, Morley found his calling in teaching. As a professor at Western Reserve College, Morley published 43 papers individually and 15 in collaborative efforts.
A scientist, benefactor and educator, Morley is generally known for his collaborative experiment with Nobel Prize winner Albert Michelson, then a physics professor at the Case School of Applied Science. Despite its great importance in the history of scientific thinking, surprisingly few people are familiar with Michelson and Morley’s research. Even fewer know of Morley’s contributions to science education or his alma mater.
From the time of Aristotle, scientists believed that the earth rotated through a stable “ether” that provided a medium for the propagation of light waves. Michelson and Morley’s research attempted to prove the existence of this ether wind.
The design for the experiment came from an idea similar to the motion of a boat in a stream. A round trip journey takes longer if the direction of movement is parallel to the current than if the trip is made perpendicularly to the flow of water. In the first case, the current will help you when rowing downstream, but severely hinder you when returning to your starting position. If you travel the same distance perpendicularly to the current, the trip takes an equal amount of time in both directions, and the total trip is shorter.
Applying this concept to the theory of light waves traveling through ether, Michelson designed an apparatus to measure the difference in a round trip travel time of two perpendicular light beams. Mirrors attached to two arms at a 90-degree angle reflected the light rays equal distances and then returned them to a common point.
Because light moves in waves, any difference in travel time would result in the appearance of an interference pattern at the point where the two light rays reconvened. Interference patterns occur when two waves collide and either becomes a smaller or larger wave due to the nature of their interaction. For this experiment, the light waves were in sync when they began their journeys, but if they traveled for different lengths of time, their crests would not match up when hey met again. A slight shift will produce an observable pattern.
Only a very minute difference between the travel times of two light beams was expected. Everything needed to be in perfect alignment to make these extremely sensitive measurements. Any slight disturbance of the equipment, a footfall for example, could produce false positive results.
Morley’s contribution to the experimental design helped solve the stability problem. He mounted the apparatus on a stone slab fixed to a wooden doughnut floating in mercury. The mercury provided a cushion as well as an easy way to rotate the apparatus. This ingenious design virtually eliminated any vibrations. In a letter to his father, Morley stated, “I have no doubt we shall get decisive results.”
The experimenters slowly rotated their apparatus, taking measurements, as Morley said, “to see if light travels with the same velocity in all directions.” The result: no interference patterns, meaning no ether. Some scientists found this hard to believe. Albert Einstein, however, used their results in the second postulate of his theory of relativity. When questioned about the influence of Michelson and Morley’s result, he said the “experiment played an important role in the development of the relativity-concept.”
In addition to his fame as a scientist, Morley also made a significant contribution to Williams itself, bequeathing the college $100,000, much of his equipment, and three honorary gold medals when he died in 1923. “It is surprising the Morley hasn’t received any recognition before this, though he gave so much,” said Professor Chip Lovett.
For over 25 years Morley worked as a professor at Western Reserve College now Case Western in Ohio. He believed that a broad foundation of knowledge was essential for building a good scientist, something that is personified in the liberal arts education at Williams.
As a professor, Morley was extremely successful and popular with the students. “He was the only one who held more than their respect. They loved him,” said a former pupil.
Morley also designed one of the first teaching laboratories. In a letter written just after its completion, he described the lab: “There is a counter running around three sides of the room with twenty-four drawers. Three shelves hold the students’ apparatus, and gas is provided for each student. It is to be a very convenient room.” Walk into the Williams’s new laboratories and you will see that the basic lab design has changed little form Morley’s days.