Morley, Edward Williams (1838-1923)

Morley, Edward Williams (1838-1923)

American physicist

Originally trained for the ministry, Edward Williams Morley decided instead in 1868 to pursue a career in science, the other great love of his life. Initially, Morley devoted himself primarily to teaching, but gradually became engaged in original research. His work can be divided into three major categories: the first two involved the determination of the oxygen content of the atmosphere and efforts to evaluate Prout's hypothesis. His third field of research involved experiments on the velocity of light, and it was this research that brought him scientific notoriety.

Morley was born in Newark, New Jersey, on January 29, 1838. His mother was the former Anna Clarissa Treat, a schoolteacher, and his father was Sardis Brewster Morley, a Congregational minister. According to a biographical sketch of Morley in the December 1987 issue of the Physics Teacher, the Morley family had come to the United States in early Colonial days and "was noted for its deep patriotism and religious devotion."

Morley's early education took place entirely at home, and he first entered a formal classroom at the age of nineteen when he was admitted to Williams College in Williamston, Massachusetts, as a sophomore. His plans were to study for the ministry and to follow his father in a religious vocation. He also took a variety of courses in science and mathematics, including astronomy, chemistry , calculus, and optics. His courses at Williams were a continuation of an interest in science that he had developed at home as a young boy.

Morley graduated from Williams as valedictorian of his class with a bachelor of arts degree in 1860. He then stayed on for a year to do astronomical research with Albert Hopkins. Morley's biographers allude to the careful and precise calculations required in this work as typical of the kind of research Morley most enjoyed doing.

After completing his work with Hopkins, Morley entered the Andover Theological Seminary to complete his preparation for the ministry, while concurrently earning his master's degree from Williams. Morley graduated from Andover in 1864, but rather than finding a church, he took a job at the Sanitary Commission at Fortress Monroe in Virginia. There he worked with Union soldiers wounded in the Civil War.

His work completed at Fortress Monroe, Morley returned to Andover for a year and then, failing to find a ministerial position, took a job teaching science at the South Berkshire Academy in Marlboro, Massachusetts. It was at Marlboro that Morley met his future wife, Isabella Birdsall. The couple was married in 1868. Morley had finally received an offer in September, 1868, to become minister at the Congregational church in Twinsburg, Ohio. He accepted the offer but, according to biographers David D. Skwire and Laurence J. Badar in the Physics Teacher, became disenchanted with "the low salary and rustic atmosphere" at Twinsburg and quickly made a crucial decision: he would leave the ministry and devote his life to science.

The opportunity to make such a change had presented itself shortly after Morley arrived in Twinsburg when he was offered a position teaching chemistry, botany, geology , and mineralogy at Western Reserve College in Hudson, Ohio. Morley accepted, and when Western Reserve was moved to Cleveland in 1882, Morley followed. While still in Hudson, Morley was assigned to a full teaching load, but still managed to carry out his first major research project. That project involved a test of the so-called Loomis hypothesis, which held that during periods of high atmospheric pressure , air is carried from upper parts of the atmosphere to the earth's surface. Morley made precise measurements of the oxygen content in air for 110 consecutive days, and his results appeared to confirm the theory.

In Cleveland, Morley became involved in two important research studies almost simultaneously. The first was an effort at obtaining a precise value for the atomic weight of oxygen, in order to evaluate a well-known hypothesis proposed by the English chemist William Prout in 1815. Prout had suggested that all atoms are constructed of various combinations of hydrogen atoms.

Morley (as well as many other scientists) reasoned that should this hypothesis by true, the atomic weight of oxygen (and other elements) must be some integral multiple of that of hydrogen. For more than a decade, Morley carried out very precise measurement of the ratios in which oxygen and hydrogen combine and of the densities of the two gases. He reported in 1895 that the atomic weight of oxygen was 15.897, a result that he contended invalidated Prout's hypothesis.

Even better known than his oxygen research, however, was a line of study carried out by Morley in collaboration with Albert A. Michelson, professor of physics at the Case School of Applied Science, adjacent to Western Reserve's new campus in Cleveland. Morley and Michelson designed and carried out a series of experiments on the velocity of light. The most famous of those experiments were designed to test the hypothesis that light travels with different velocities depending on the direction in which it moves, a hypothesis required by current theories regarding the way light is transmitted through space . A positive result for that experiment was expected and would have confirmed existing beliefs that the transmission of light is made possible by an invisible "ether" that permeates all of space.

In 1886, Michelson and Morley published their report of what has become known as the most famous of all negative experiments. They found no difference in the velocity with which light travels, no matter what direction the observation is made. That result caused a dramatic and fundamental rethinking of many basic concepts in physics and provided a critical piece of data for Albert Einstein's theory of relativity.

The research on oxygen and the velocity of light were the high points of Morley's scientific career. After many years of intense research, Morley's health began to deteriorate. To recover, he took a leave of absence from Western Reserve for a year in 1895 and traveled to Europe with his wife. When he returned to Cleveland, he found that his laboratory had been dismantled and some of his equipment had been destroyed. Although he remained at Western Reserve for another decade, he never again regained the enthusiasm for research that he had had before his vacation.

Morley died on February 24, 1923, in West Hartford, Connecticut, where he and Isabella had moved after his retirement in 1906; she predeceased him by only three weeks. Morley was nominated for the Nobel Prize in chemistry in 1902, and received a number of other honors including the Davy Medal of the Royal Society in 1907, the Elliot Cresson Medal of the Franklin Institute in 1912, and the Willard Gibbs Medal of the Chicago section of the American Chemical Society in 1917. He served as president of the American Association for the Advancement of Science in 1895 and of the American Chemical Society in 1899.

See also Atmospheric chemistry; Atmospheric composition and structure; Quantum theory and mechanics