holography \ho-'la-gr9-fe\ Method of recording or reproducing a three-dimensional image, or hologram, by means of a pattern of interfer¬ ence produced using a laser beam. To create a hologram, a beam of coher¬ ent light (a laser) is split; half the beam falls on a recording medium (such as a photographic plate) unaltered, and the other half is first reflected off the object to be imaged. The two beams together produce an interference pattern of stripes and whorls on the plate. The developed plate is the holo¬ gram. When light is shone on the hologram, a three-dimensional image of the original object is produced by the recorded interference pattern. Some holograms require laser light to reproduce the image; others may be viewed in ordinary white light. Holography was invented in 1947 by the Hungarian-British physicist Dennis Gabor (1900-1979), who won a 1971 Nobel Prize for his invention.
Holst, Gustav(us Theodore von) (b. Sept. 21, 1874, Cheltenham, Gloucestershire, Eng.—d. May 25, 1934, London) British composer. The son of an organist, he studied at the Royal College of Music. There he met Ralph Vaughan Williams, who became a friend for life. He made his living first by playing trombone, then as a teacher. Always frail, after a collapse in 1923 he gave up teaching to devote the rest of his life to com¬ position. His most popular piece is the vividly orchestrated suite The Planets (1916); other works include the charming St. Paul’s Suite for strings (1913), the Hymn of Jesus (1917), and the Choral Fantasia { 1930).
Holstein \'hol-sten\ or Holstein-Friesian \'fre-zhon\ Breed of large dairy cattle that originated in northern Holland and Friesland. Its chief characteristics are its large size and black-and-white-spotted markings, sharply defined rather than blended. Probably selected for their dairy qualities c. 2,000 years ago, they have long been distributed over the fer¬ tile lowlands of continental Europe. In the U.S., Holsteins outnumber all other dairy breeds and produce 90% of the milk supply. Their milk has a relatively low butterfat content.
Holstein See Schleswig-Holstein
Holstein Yhol-,shtm\, Friedrich (August) von (b. April 24, 1837, Schwedt an der Oder, Pomerania—d. May 8, 1909, Berlin, Ger.) German diplomat. A member of the German foreign office from 1876, he never became foreign minister but exercised power behind the scenes, earning the nickname “the Gray Eminence.” He broke with Otto von Bismarck over his alignment with Russia, as Holstein advocated a firm alliance with Austria and Britain. After Bismarck’s dismissal in 1890, Holstein advised against the renewal of the Reinsurance Treaty. He held important posts under Chancellors Leo, count von Caprivi, Chlodwig, prince zu Hohenlohe- Schilungfurst, and Bernhard, prince von Bulow, but he proved powerless to oppose the policies of Emperor William II and was dismissed in 1906.
Holy Alliance Loose organization of most of the European sovereigns, formed in 1815 by Alexander I of Russia, Francis I of Austria, and Fred¬ erick William III of Prussia, after the final defeat of Napoleon. Its avowed purpose was to promote the influence of Christian principles in the affairs of nations, but it accomplished little and became a symbol of conserva¬ tism and repression in central and eastern Europe. See also Congress of Laibach.
Holy Communion See Eucharist Holy Grail See grail Holy Island See Lindisfarne
Holy League (1576-98) Association of Roman Catholics during the French Wars of Religion. It was first organized under the leadership of the 3rd duke de Guise, to oppose concessions granted to the Protestant Hugue¬ nots by Henry III. In 1584, when the Huguenot leader Henry of Navarra (later Henry IV) became heir to the throne, the Holy League set up an alter¬ native candidate, with Spain’s assistance. To put an end to the league, which challenged his authority, Henry III had the duke de Guise assassi¬ nated (1588), an act that, rather than destroying the League, led to Henry’s own assassination in 1589. The league opposed the accession of Henry IV, but its power waned when he became a Roman Catholic in 1593.
Holy of Holies Innermost and most sacred area of the ancient Temple of Jerusalem, accessible only to the Israelite high priest and only once a year, on Yom Kippur. The Holy of Holies was located at the western end of the temple. At its entrance stood a small cedar altar overlaid with gold. In the First Temple (see Temple of Jerusalem) the Holy of Holies held the Ark of the Covenant.
Holy Roman Empire German Heiliges Romisches Reich Realm of varying extent in medieval and modem western and central Europe. Traditionally believed to have been established by Charlemagne, who was crowned emperor by Pope Leo III in 800, the empire lasted until the renunciation of the imperial title by Francis II in 1806. The reign of the German Otto I (the Great; r. 962-973), who revived the imperial title after Carolingian decline, is also sometimes regarded as the beginning of the empire. The name Holy Roman Empire (not adopted until the reign of Frederick I Barbarossa) reflected Charlemagne’s claim that his empire was the successor to the Roman Empire and that this temporal power was augmented by his status as God’s principal vicar in the temporal realm (parallel to the pope’s in the spiritual realm). The empire’s core consisted of Germany, Austria, Bohemia, and Moravia. Switzerland, the Nether¬ lands, and northern Italy sometimes formed part of it; France, Poland, Hungary, and Denmark were initially included, and Britain and Spain were nominal components. From the mid-11th century the emperors engaged in a great struggle with the papacy for dominance, and, particu¬ larly under the powerful Hohenstaufen dynasty (1138-1208, 1212-54), they fought with the popes over control of Italy. Rudolf I became the first Habsburg emperor in 1273, and from 1438 the Habsburg dynasty held the throne for centuries. Until 1356 the emperor was chosen by the German princes; thereafter he was formally elected by the electors. Outside their personal hereditary domains, emperors shared power with the imperial diet. During the Reformation the German princes largely defected to the Protestant camp, opposing the Catholic emperor. At the end of the Thirty Years' War, the Peace of Westphalia (1648) recognized the individual sov¬ ereignty of the empire’s states; the empire thereafter became a loose fed¬ eration of states and the title of emperor principally honorific. In the 18th century, issues of imperial succession resulted in the War of the Austrian Succession and the Seven Years' War. The greatly weakened empire was brought to an end by the victories of Napoleon. See also Guelphs and Ghi- bellines; Investiture Controversy; Concordat of Worms. See table on fol¬ lowing page.
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888 I Holy Spirit ► Homer
Holy Roman Emperors
Carolingian dynasty
Henry Raspe
1246-47
Charlemagne
William of Holland
1247-56
(Charles 1)
800-14
Conrad IV
1250-54
Louis 1
814-40
Great Interregnum
Civil War
840-43
Richard
1257-72
Lothair 1
843-55
Alfonso (Alfonso X
Louis II
855-75
of Castile)
1257-75
Charles II
875-77
House of Habsburg
Interregnum
877-81
Rudolf 1
1273-91
Charles III
881-87
House of Nassau
Interregnum
887-91
Adolf
1292-98
House of Spoleto
House of Habsburg
Guy
891-94
Albert 1
1298-1308
Lambert
894-98
House of Luxembourg
Carolingian dynasty