HELENA 498 HELL cotton oil, boxes, cotton goods, ma- chinery, canned goods, and finished lum- ber. It has electric lights, public schools, public library, the Jefferson High School, Sacred Heart Academy, daily and weekly newspapers, and a National bank. Pop. (1910) 8,722; (1920) 9,112. HELENA, a city of Montana, and county-seat of Lewis and Clarke co., near Prickly Pear creek, and on the Great Northern, and the Northern Paci- fic railroads. It is the commercial center of Montana, northern Idaho, and east- ern Washington, and has abundant water power from the Missouri river. It has numerous smelting and reduction works, blast furnaces, foundries, machine shops, granite and sandstone works, and does considerable business in mining, farm- ing, and stock-raising. It is the seat of Montana Wesleyan University, Mount St. Charles College, State Capitol, Fed- eral Buildings, Assay Office, St. Vin- cent's Academy, Orphans' Home, St, Peter's and St. John's Hospitals. The city has electric lights, and electric street railroads connecting with surrounding towns, daily and weekly newspapers, public library, 2 National banks. Pop. (1910) 12,515; (1920) 12,037. HELICTIS (hel-ik'tis), a genus of carnivorous quadrupeds, allied to the skunks, of which there are at least two species, one (H. moschata) found in China, the other {H. onentalis) in Nepal. HELIGOLAND, or HELGOLAND (hel'ig-a-land), a small island in the North Sea, formerly belonging to Great Britain. It is about 1 mile long from N. to S., and 1-3 of a mile from E. to W.; 1-5 of a square mile in superficial area, and about 2 2-3 miles in circumference. The island consists of an upper and a lower quarter, the Oberland and Sandy Island. A lighthouse stands on a cliff near the village. Heligoland is an im- portant place in time of war, and com- mands the German trade in the North Sea. The island, which was taken by the English from the Danes in 1807, was formally ceded to Great Britain in 1814, and by Great Britain to Germany in 1890. Pop. about 3,000. The Germans made Heligoland an impregnable for- tress and military base. In the Bight the British won a naval victory over the Germans, Aug. 28, 1914. By the terms of the Treaty of Versailles the fortifi- cations of Heligoland were dismantled. HELIOPOLIS (hel-e-op'o-lis), the On, Rameses, or Beth-shemesh of the Hebrew Scriptui-es; now called Matarich; situ- ated a little N. of Memphis; and one of the most ancient and extensive cities of Egypt under the Pharaohs. It had a magnificent temple dedicated to Ra, and communicated with the Nile by lakes and canals. During the flourishing ages of the Egyptian monarchy the priests taught within the precincts of its tem- ples, and both Eudoxus and Plato visited its famous schools. Here Joseph and Mary are said to have rested with the in- fant Christ. Near the village stands the Pillar of On, supposed to be the oldest Egyptian obelisk, 67^ feet high, and 6 feet broad at the base. The Turks were defeated here by the French in 1800. HELIUM, a gaseous element. Atomic weight 3-99. Discovered in 1868 by means of the spectroscope, in the sun, by Jannsen and Lockyer, the discovery of terrestrial helium was made later by Ramsay, in the gases evolved from the mineral cleveite. It is widely distrib- uted, but occurs in small quantities. It is present in the air to the extent of about one volume of helium in 250,000 volumes of air, occurs in many minerals, and has been found in the gases from hot mineral springs. Ramsay found that the emanations from radium showed the presence of helium, and it is believed to be the final product of the disintegration of radium. It was considered of purely academic interest until 1915, when the suggestion was made in England that it should be used in place of hydrogen in balloons and airships. Its density is al- most twice that of hydrogen, but owing to its chemical inertness and non-inflam- mability its use for this purpose was thought worthy of consideration. The matter was brought to the attention of the United States Bureau of Mines and this led to the development of the Jef- feries-Norton and Linde processes for the extraction of helium from natural gas, which consists mainly of nitrogen, methane and helium. By freezing the gas at a temperature of 318° F. below zero, the other gases become liquified, while helium remains in the gaseous con- dition, and can be drawn off. A yield of 1 per cent, is considered satisfac- tory. At the time of the signing of the Armistice, quantities of the gas were loaded on the docks at New Orleans, ready for shipment to France. HELL, a place of punishment, found, with more or less distinctness, in nearly all ethnic forms of religion, the precise nature of the punishment varying widely. Three definite stages in the concept of hell may be traced ; (1 ) a vague notion of a fu- ture life, to be spent in misery, with lit- tle or no idea of moral retribution; (2) it ranks as a place of torment for those