James Melville Gillis was born on September 6, 1811, in Georgetown, Washington, DC, to George Gillis and Mary Melville. He joined the navy in 1827 as a midshipman and spent the next several years aboard the USS Delaware, the USS Java, and the USS Concord. In 1833, he passed his examinations and became a passed midshipman.

In the early 1830s, he reportedly overheard someone telling members of Congress that naval officers were incapable of performing scientific duties. To prove him wrong, Gillis requested a leave of absence to enroll at the University of Virginia in 1833. He studied modern languages, mathematics, and natural philosophy. Despite his experience in the navy, Gillis chafed at the university’s strict regulations. He violated the early-rising rule and the uniform rule and attended a meeting protesting a new curfew in November 1833. Students posted handbills around grounds advertising the meeting, which would “take into consideration the propriety of Rebelling” against the university’s rules. The faculty locked the door to the meeting room, but students broke in through the window. Tempers flared, and the faculty recommended censuring the students, but they ultimately resolved the crisis peacefully. The faculty affirmed students’ right to hold “regular and orderly” meetings, while the students agreed not to “meet in any particular room without permission.” 

Gillis’s study habits caused severe eye inflammation, which forced him to withdraw from the university in 1835. His eyes recovered after several weeks in a dark room, and he travelled to Paris to resume his studies. He stayed until the spring of 1836, when he returned to the naval service. In November 1836, the navy transferred him from the Navy Yard in Philadelphia to the Depot of Charts and Instruments in Washington, DC, and he was placed in charge of the depot in June 1837.

Gillis married Rebecca Stokes Roberts around 1837, and they had six children: Rebecca, born 1838; James, born 1840; John, born 1842; Fannie, born 1843; William, born 1844; and George, born 1848. His youngest son died of scarlet fever in 1853. During the early 1840s, Gillis worked tirelessly to establish the institution that would become the United States Naval Observatory. As he later explained, “I should have regarded it as time misspent to labor so earnestly only to establish a depot. My aim was higher.” By enabling naval officers to pursue the “highest known branch of science,” he hoped to “compel an acknowledgement of abilities hitherto withheld from the service.” He shared his plan with the navy in 1841, and by August 1842 he had succeeded in pushing a bill through Congress appropriating $25,000 for his cause.

He personally travelled to Europe to purchase instruments, and by 1844 the observatory was ready for service. Gillis took part in the United States Astronomical Expedition in South America from 1849 to 1852, and visited Peru in August 1858 and Washington Territory in 1860 to observe total solar eclipses. He published extensively and was one of the original members of the National Academy of Sciences. 

Gillis remained loyal to the Union, and in the summer of 1861, President Abraham Lincoln appointed him as a commander on the reserved list in the United States Navy. He became superintendent of the Naval Observatory during the Civil War, and according to one biographer he turned it into “one of the few first-class observatories in the world.” He achieved the rank of captain in July 1862 and spent the war producing charts and instruments for the navy’s operations against Confederate ports. Two of his sons served in the Union war effort: James became a 2nd lieutenant in the regular army, while John worked as a civilian assistant for the army’s engineering department. Gillis died of a stroke on February 9, 1865, in Washington, DC, one day after his son James returned home from a Confederate prison camp. He was buried in Oak Hill Cemetery.

Image: James Melville Gilliss (Appleton's Cyclopædia of American Biography, v. 2 (1888), p. 653).