Peter Dirck Keyser

Peter Dirck Keyser (born in Philadelphia, Pennsylvania, 8 February 1835; died same place, 8 March 1897) was a United States ophthalmologist.

He studied at Delaware College until 1851, when he entered the chemical laboratory of Frederick A. Genth, and there made analyses of minerals, the results of which were published in the American Journal of Science, and were afterward incorporated in Dana's Mineralogy. In 1856 he went to Germany and pursued professional studies for two years.

Soon after the beginning of the Civil War he became captain in the 91st Pennsylvania Regiment, and served with the Army of the Potomac until after the Battle of Fair Oaks. Failing health then led to his resignation.

He returned to Germany, where he studied at the University of Munich, and then at that of Jena, receiving there the degree of M.D. in 1864. On his return to the United States, he was appointed acting assistant surgeon in the U.S. Army, and was detailed to Cuyler Hospital in Germantown, Pennsylvania. In 1865 he resigned from the service to enter on his private practice.

On April 15, 1865, Keyser was one of three co-Founders of the Military Order of the Loyal Legion of the United States, or MOLLUS. It was the first post-Civil War veterans' organization, and was open to men who had served in the suppression of the Rebellion and who had held a commission in the armed forces of the United States. He was assigned MOLLUS insignia number 00003. The organization exists today, composed largely of the descendants of those officers.

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