ALTOONA  , a

city of Blair county, Pennsylvania, U.S.A., about 117 M . E. by N. of Pittsburg . Pop . (189o) 30,337; (1900) 38,973, of whom 3301 were foreign-born, 1518 being German; (1910) 52,127 . It lies in the upper end of Logan Valley at the base of the Alleghany mountains, about 118o ft. above sea-level, and commands views of some of the .most picturesque mountain scenery in the state . A short distance to the W. is the famous Horseshoe Bend of the Pennsylvaniarailway . Altoona is served by the Pennsylvania railway, and is one of the leading railway cities in the United States . Its freight yard is 7 M. long, and has 221 M. of tracks . Large numbers of eastbound coal trains from the mountains and westbound " empties " returning to the mines stop here; and the cars of these trains are classified here and new trains made up . Locomotives and cars are sent to Altoona to be repaired from all over the Pennsylvania railway system E. of Pittsburg, and cars and locomotives are built here; and in the south Altoona foundries car wheels and general castings for locomotives and cars are made . The several departments of railway work are used to give training in a sort of railway university . Graduates of technical schools are received as special apprentices and are directed in a course of four years through the erecting shops, vice shop, blacksmith shop, boiler shop, roundhouse, test department, machine shop, air-brake shop, iron foundry, car shop, work of firing on the road, office work in the motive power accounting department, and drawing room; the most competent may be admitted through the grades of inspector, in the office of the master mechanic or of the road foreman of engines, assistant master mechanic, assistant engineer of motive power, master mechanic and superintendent of motive power .

The Pennsylvania railway, co-operating with the public school authorities, established at Altoona, in 1907, a railway high school, the first institution of the

kind in the country . It has a well-equipped drawing room, carpenter shop, forging room, foundry, science laboratories and machinery department, in which expert instruction is given . In 1905 the city's factory products were valued at $14,349,963, and in this year the railway shops gave employment to 83'7 % of all wage-earners employed in manufacturing establishments . The manufacture of silk is the only other important industry in the city . The site of the city (formerly farming land) was purchased in 1849 by the Pennsylvania Railroad Company and was laid out as a town . It was incorporated as a borough in 1854 and was chartered as a city in 1868 . ALTO-RELIEVO (Ital. for " high relief "), the term applied to sculpture that projects from the plane to which it is attached to the extent of more than one-half the outline of the principal figures, which may be nearly or in parts entirely detached from the background . It is thus distinguished from basso-relieve (q.v.), in which there is a greater or less approximation in effect to the pictorial method, the figures being made to appear as projecting more than half their outline without actually doing so . At the same time it is not only the actual degree of relief which is implied by these two terms, but a resultant difference also of design and treatment necessitated by the contingent differences of light and shadow .