Major Philip Sidney Coolidge (1830 – 1863)

Major Philip Sidney Coolidge. Photography courtesy of the Library of Congress.

On September 19, 1863, Major Philip Sidney Coolidge died leading the 16th U.S. Infantry into battle at Chickamauga, presumably. A great-grandson of Thomas Jefferson on his mother’s side, and a man who by all accounts lived “a strangely roving adventurous life,” Boston newspapers disagreed over his fate into the early months of 1864. First, he was reported to have died. Then, later articles suggested he was instead wounded and captured. Then, they again reported on his death until finally the Union Army listed his official status as “missing in action.” His twin brother Algernon Coolidge, a surgeon working with the U.S. Sanitary Commission, traveled to the front to make inquiries with little success. His uncle, the Confederate Secretary of War, intervened on the family’s behalf. More than a year later, Union General Benjamin Butler returned Coolidge’s sword to the family, a gift from his youngest brother and inscribed with his name. His body was never recovered, and though his fate was all but certain, the Coolidge family continued to search for answers more than two years after his probable death.

Theirs was not a unique story. In a war where 620,000 men died (and this the conservative estimate), neither the Union or Confederate armies had a formal system in place to notify next of kin when a soldier died. Neither army issued an official dog tag, or anything of the like, and there was no guarantee that the bodies of lost soldiers would be formally identified much less returned to their families. Civil War armies lacked formal structures to account for casualties after battle. Union regulations required commanders to provide handwritten lists of missing, wounded, and killed men alongside their official battlefield reports, but these accounts were frequently inaccurate. After the war, federal employees reinterred more than 300,000 Union soldiers buried in southern battlefields, creating 73 national cemeteries, though only 60 percent of the remains were formally identified. If Coolidge’s body was among those recovered, he fell within the 40 percent who were not.

Philip Sidney Coolidge first connected with the Harvard College Observatory in 1853 when he joined the U.S. Expedition for the survey of the North Pacific Ocean and China Sea as both an astronomer and engineer. His association with the Observatory spanned seven years, though financial constraints meant he never received a formal paycheck. In 1855, he led the chronometric Expedition of the U.S. Coast Survey between Cambridge, MA and Liverpool, England “having for its object to ascertain the relation of the European and American systems of longitude.” His work was instrumental in the determination of the zero longitudes of the western continent. He did extensive survey work in Arizona and Mexico, where his voluntary participation in a revolutionary uprising landed him in a Mexico City prison for a few months. Born in Boston, but educated in France and then at a military college in Dresden, he spoke English with a French accent. Nathaniel Southgate Shaler, a noted Harvard geologist and friend, later observed, “[Coolidge] was a rather small, delicate person, with a soldierly courage, with a gentle pale face, and a large nose adorned with eye-glasses.”

It seems few held Coolidge in higher esteem than George Philips Bond. The pair worked together under the tutelage of Bond’s father, the founding Director of the Harvard College Observatory. Coolidge then briefly served as an assistant to the younger Bond when he assumed the Directorship until he left his post to accept a position with the Union Army. They would not see each other again. It was Bond who wrote an extended obituary for Coolidge, published in the Boston Daily Advertiser on January 2, 1864. Bond spoke plainly of his friend’s “adventurous and high-spirited nature,” which might’ve erroneously disguised his equally impassioned “disposition to engage seriously in scientific pursuits.” It was this “generous enthusiasm” and “a warm and almost personal affection” for the Observatory’s interests that led Coolidge to consecrate “the best hours of his life to its service.” In the 1864 Director’s Report, Bond wrote another memorial to Coolidge despite the “painful anxiety which had been awakened” regarding his fate. He again spoke of the man’s “characteristic zeal” towards the workings of the Observatory, which is all the more evident in the work Coolidge left behind.

The Wolbach Library maintains a collection of historical notebooks, now known as Project PHaEDRA. Digital copies of the Project PHaEDRA notebooks are available online, and provide unique insight into early astronomical research. Coolidge’s touch is unmistakable. Between hand-drawn planetary diagrams and tables of astronomical data, Coolidge added a little humor. Select examples are included below:

A cartoon drawing of W.C. Bond and G.P. Bond by HCO assistant Philip Sidney Coolidge. c. 1857
Drawing of Saturn by Philip Sidney Coolidge. c. 1855

The most detailed account of Coolidge’s death came later. Of the 1,662 Harvard-associated men who fought in the Civil War, 304 of them fought for the Confederacy. Among them, was Leslie Waggener, a recent graduate from Kentucky and a friend of both Nathaniel Shaler and Philip Sidney Coolidge. In 1874, while working as a state geologist in Kentucky, Shaler reunited with Waggener by happenstance, both having mistakenly believed the other to have died in the war. In Shaler’s own words:

“Waggener was the first to recover his balance enough to start conversation. He began by asking me something about Coolidge, who was killed at Chickamauga. Then he told me the reason for his question. The story ran as follows. Waggener was with the force that broke the Federal line where the Sixteenth Infantry was stationed; as the shattered remnant went back, he saw Coolidge standing in his place with the point of his sword up, making what the soldiers called a “defy.” Waggener recognized him, knew that his signal of no surrender would quickly lead to his being shot, and ran toward him. When he was a few score feet away, he was himself shot, and did not recover consciousness for some days thereafter.”

Philip Sidney Coolidge was thirty-three when he died. Every account of his life makes note of his unique character which propelled him again and again towards adventure. Shaler put this way, “I have seen much of men, but never another who was as curiously interesting as this son of an ancient and staid Boston family. He had roamed about afoot in various terrestrial wilds and was seeking celestial realms.”

** This article highlights a singular perspective during the Civil War relating to the history of the Harvard-Smithsonian Center for Astrophysics. The opportunities Philip Sydney Coolidge received both in his time at the Harvard College Observatory and in the Union Army were not equally available to all people, so there are many stories we cannot meaningfully tell in the history of our institution. Roughly 186,000 Black men fought for the Union Army during the Civil War. For further reading on their experiences of the war, please see:

  • Baumann, Susan K. Black Civil War Soldiers. New York, NY: Rosen Publishing Group, 2013.
  • Gooding, James Henry, and Virginia M. Adams. On the Altar of Freedom : A Black Soldier’s Civil War Letters from the Front. Amherst: University of Massachusetts Press, 1991.
  • Mendez, James G. A Great Sacrifice. 1st ed. The North’s Civil War. New York: Fordham University Press, 2019.

Bond, George Philips. “Memorial of Major Sidney Coolidge,” Published in the Boston Daily Advertiser, 2 Jan. 1864.

Bond, George Phillips, Philip Sidney Coolidge, William Cranch Bond, Charles W. Tuttle, Truman Henry Safford. Equatorial, Volume 3. 1855, pg. 54. [phaedra0173] Cambridge. MA: John G. Wolbach Library, Harvard College Observatory. Project PHaEDRA. Harvard College Observatory observations, logs, instruments readings, and calculations.

Bond, George Phillips. “Report of the Committee of the Overseers of Harvard College Appointed to Visit The Observatory in the Year 1863: Together with Report of the Director.” Boston: Press of Geo. C. Rand & Avery S Cornhill, 1864.

Coolidge, Philip Sidney, George Phillips Bond, and Horace Tuttle. Equatorial. 1857, pg. 3. [phaedra0178] Cambridge. MA: John G. Wolbach Library, Harvard College Observatory. Project PHaEDRA. Harvard College Observatory observations, logs, instruments readings, and calculations.

Faust, Drew Gilpin. This Republic of Suffering: Death and the American Civil War (New York: Alfred A. Knopf, 2012), 251-252.

Major Sidney Coolidge, U.S.A., in uniform, full-length portrait, facing front. United States [Oswego, NY: Meylink’s Union, between 1861 and 1863] Photograph. Courtesy of Library of Congress.

Shaler, Nathaniel Southgate. Autobiography of Nathaniel Southgate Shaler (Classic Reprint). Forgotten Books, 2015.