HEAP, Gwynn Harris, diplomatist, born in Chester, Pennsylvania, 23 March, 1817; died in Constantinople, Turkey, 6 March, 1887. His great-grandfather, George, was sent by the British government to Pennsylvania as surveyor-general. One of the earliest maps of Philadelphia was made by him, and is preserved in the Pennsylvania library in that city. In 1839-'40 Gwynn served as vice and acting consul in Tunis, where his father had been appointed consul in 1825. He was appointed a government clerk in Washington, D. C., in 1846, and in 1855-'7 was employed by the war department in Turkey in the purchase of camels, hi 1861, being then a clerk in the navy department, he volunteered for secret service at Pensacola, Florida, and in 1863-'4 had charge of the pilots of Admiral Porter's squadron on the Mississippi. He was appointed consul at Belfast, Ireland, in 1866, and the following year sent to Tunis as consul, where he remained until 1878. In that year he was made secretary of legation and .consul-general at Constantinople, occasionally serving as charge d'affaires. During his official residence in Tunis he organized the department devoted to that country in the Centennial exhibition at Philadelphia in 1876. Mr. Heap compiled "A Synoptical Index to the Statutes at Large" (1849-'50), and is the author of " Exploration of the Central Route to the Pacific" (Philadelphia, 1853) and "Itinerary of the Central Route to the Pacific" (1854).--His son, David Porter, engineer, born in San Stefano, Turkey, 24 March, 1843, was educated at Georgetown college, D. C., and at the United States military academy, where he was graduated in 1864. He was assigned to the engineer corps, served in the civil war in the Army of the Potomac, and was brevetted captain, 2 April, 1865, "for gallant and meritorious services." He was promoted captain, 7 March, 1867, and major of engineers, 23 June, 1882. Since the war he has been engaged in the construction of fortifications, the improvement of harbors, and other duties. In 1871 he was engaged in the exploration of the region afterward known as the Yellowstone park, and in 1876 had charge of the engineering section of the war department exhibit at the Philadelphia centennial exhibition. In 1881 he was ordered on detached service as military representative of the United States at the Paris congress of electricians, and honorary commissioner to the Paris electrical exhibition. Major Heap has travelled extensively in Europe, Asia, Africa, and North America. He is the author of a " History of the Application of the Electric Light to Lighting the Coasts of France" (Washington, D.C., 1883); " Report of Engineer Department of the Philadelphia Exhibition" (1884); "Electrical Appliances of the Present Day" (New York, 1884); and " Ancient and Modern Lights" (Boston. 1887).