James Melville Gilliss, astrónomo que encabezó la expedición que se instaló en Santiago buscando realizar un paralaje solar en conjunto con otros observatorios del Hemisferio Norte.
English: GILLISS, James Melville, astronomer, born in Georgetown, D. C., 6 September, 1811; died in Washington, D. C., 9 February, 1865. He entered the United States navy as a midshipman at the age of fifteen, and made his first cruise on the "Delaware." Subsequently he served on the "Concord" and on the "Java," and in 1831, after an examination, was advanced to passed midshipman. To obtain a scientific education he spent a year in the University of Virginia, and later pursued higher studies in Paris. In 1836 he became assistant in the depot of charts and instruments in Washington, and soon afterward was given charge of the small wooden building, which was then the only observatory in Washington. Soon after the sailing of the United States exploring expedition under Captain Charles Wilkes, he received special instructions from the secretary of the navy concerning the determination of differences of longitude by means of moon-culminations, occultations, and eclipses, with magnetic and meteorological observations. His active astronomical career began with this work, and Dr. Benjamin A. Gould says in this connection" "It was Gilliss who first in all the land conducted a working observatory, he who first gave his whole time to practical astronomical work, he who first, published a volume of observations, first prepared a catalogue of stars, and planned and carried into effect the construction of a working observatory as contrasted with one intended chiefly for purposes of instruction." He was made lieutenant in February, 1838, and until the return of the expedition was active in making observations of every culmination of the moon and every occultation visible in Washington that occurred between two hours before sunset and two hours after sunrise. His report on the "Astronomical Observations made at the Naval Observatory" (Washington, 1846) was the first to be published in the United States. In August, 1842, a bill was passed by congress, authorizing the establishment of an astronomical observatory, and the duty of preparing the plans for a building and arranging for the instruments was assigned to Lieutenant Gilliss. After consulting American astronomers he visited Europe, where he studied the latest forms of apparatus, and on his return began the erection of the building, had the instruments mounted and essentially adjusted, and a library procured, all within eighteen months. The superintendence of the new building was given to Lieutenant Matthew F. Maury, while Lieutenant Gilliss was assigned to duty on the coast survey in reducing for its use the entire series of moon-culminations previously observed and published by him. Fifteen manuscript folio volumes in the archives of the survey contain this valuable work. From November, 1848, till October, 1852, he was engaged in making observations for the determination of the solar parallax. A station was established in December, 1849, on the hill of Santa Lucia, in Santiago, Chili, where he completed a series of observations of great value. He likewise accumulated a vast amount of information concerning earthquakes and other subjects, and the establishment of a national observatory in Chili is due to his influence. On his return he published "The United States Astronomical Expedition to the Southern Hemispheres in 1849-'52" (2 vols., Washington, 1855 et seq.). He visited Peru in August, 1858, for the purpose of observing the total eclipse of the sun of that year, and, notwithstanding his prostration with a fever, he directed the mounting of the instruments and obtained satisfactory results from his observations. His report was published by the Smithsonian institution as "An Account of the Total Eclipse of the Sun on September 7, 1858" (Washington, 1859). In 1860 he observed the total eclipse of the sun in Washington territory. After the departure of Comd'r Maury from Washington in April, 1861, Lieutenant Gilliss was assigned to the charge of the observatory in Washington. Under him it became one of the few first-class observatories in the world. He found a vast amount of work left in arrears by his predecessor, no reduction of the observations of the previous six years having been made. Lieutenant Gilliss applied himself to the work of completing them and of adding new and valuable observations with such assiduity that he gained a high reputation among the eminent astronomers of the world, he made many valuable improvements in the instruments used in astronomy, and was the author of various government reports. Lieutenant Gilliss was one of the original members of the National academy of sciences.