The city's first gas works date from Feb. 8, 1836. After the consolidation, the combined gas plants were placed under the management of trustees. Political scandals arose and the works were transferred to a bureau of gas; then, by lease, to the United Gas Improvement company, which renewed the lease, Jan. 1, 1928, for ten years, at a rental of $4,200,000 a year, or 7% on $6o,000,000. The Philadelphia Electric com pany, now consolidated with the United Gas Improvement com pany, supplies the electric current for light and power. Work on the $52,000,000 hydro-electric plant of the company at Cono wingo, Md., was begun in March 5926 and on March 1, 1928, the first power from its turbines was sent to Philadelphia over two 220,000 volt three-phase lines.
The population of Philadelphia on April 1, 1930, was 1.950,961, according to the United States census figures. First Philadelphia population figures were: (i753) 14,563; (I769) 28,043. Philadelphia's official figures, by decades, follow: (1790) 28,522; (1800) 41,,220; (1820) 63,802; (1840) 93,665; (1860, after consolidation) 565,529; (1880) 847,170; (1900) 1,293,697; (1910) 1,549,008; (1920) 1,823,779. In 1930, foreign-born whites numbered 328,624; negroes, 219,599. The 1933 population was estimated at 1,972,700.
20th century growth is measured by its demolitions—a paradox readily understood when it is explained that, in the part of the city planned by Penn, during five years (1923-27 inclusive) 3,242 dwellings and 868 other houses were demolished to make room for larger buildings, mainly commercial, and wider streets. Of the 433,796 buildings in the city in 1934, 369,238 were single family houses accommodating 72.7% of the population. There were 679 buildings over eight-family occupied by 20,328 families. Subway development has increased the tendency toward multiple-family dwellings.
The Philadelphia of today has many times more Federal offices and employees than it had when it was the Federal city. The U.S. Government has increased its property holdings ten-fold since 1900. The greatest development is the League island navy yard which includes the largest aircraft factory in the world covering 46 acres and containing nearly a million square feet of floor space, a drydock 1,064 by 210 feet capable of holding the largest ship afloat, and a storehouse with over i o acres of floor space.
Local developments since the sesquicentennial celebration of 1926 include the Locust St. and South St. subways, the opening of a convention hall, the initiation of opera and ballet companies, and railway electrification.
The central city is a rela tively small area but its influence expands over a large territory. Metropolitan Philadelphia contained 2,847,148 people within an area of 993.89 sq.m. in 1930 and there were over six million with an eighty mile radius. This section constituted a Tri-State region with 41 towns and cities, 21 in Pennsylvania, 18 in New Jersey and 2 in Delaware. Trenton was the largest of the included cities with a population of 123,356; Camden had 118,700; Wil mington, 106,597; Chester, 59,164 ; Atlantic City, 66,198 ; Lan caster, 59,949; Norristown,
; Lebanon, 25,561 and Potts town, 19,430. (G. MN.) BIBLIOGRAPHY.—FOr recent statistical material on Philadelphia, see The Bulletin Almanac and Year Book (1924-1937) ; J. Jackson, Encyclopedia of Philadelphia, 4v.
Bureau of Municipal Research, Philadelphia's Government (1932) ; Philadelphia Business Progress Association, Publications (1929-1931) ; Philadelphia Board of Trade, Annual Reports (1933-1937) and Commerce and Industry (1922-1937); and the reports of the various city departments; E. P. Allinson and B. Penrose, Philadelphia, 1681-1887, a history of municipal development (1887) ; E. P. Oberholtzer, Literary History of Phila delphia (1906) ; H. D. Eberlein and H. M. Lippincott, Colonial Homes of Philadelphia (1912) ; F. H. Taylor and W. H. Schoof, The Port and City of Philadelphia (1912) ; E. R. Pennell, Our Philadelphia (with 105 lithographs by Joseph Pennell, 1914) ; J. T. Faris, Romance of Old Philadelphia (1918) ; R. Shackelton, Book of Philadelphia (1918) ; C. Morley, Travels in Philadelphia (1920) ; G. E. Nitzsche, Philadelphia; guide to the city (1920) ; G. Barton, Little Journeys Around Old Phila delphia (1925) ; H. M. Lippincott, Philadelphia (1926) ; and, Publica tions of the City Historical Society of Philadelphia (1908-27, 3 vol.).