Fraunhofer, Joseph

frown'ho-fer, Joseph (1787-1826), a German optician of Munich. He was brought up as a maker of looking-glasses and a grinder of lenses. When a young man he held various positions as an instructor in mathematics, but ultimately became a member of a firm of manufacturers of optical instruments. He invented a machine for grinding the surface of an object glass with greater accuracy than can be attained by hand methods. He also designed various improvements in the manufacture of glass for optical purposes. In experimenting as to the best method of producing microscopes and telescopes, he was led to study the spectrum,--the band of light in many colors that is produced by causing a beam of white light to pass through a prism. He made a special study of the dark lines of the spectrum, to which the name of Fraunhofer's lines has been given. His investigations led to the invention of the spectroscope, on which we depend for our knowledge of the make-up of the sun and stars. He discovered and chartered the dark lines that occur in the spectrum of sunlight. See Spectroscope

Frederick Barbarossa (1121-1190), Frederick I, emperor of Germany. He was crowned at Aix-la-Chapelle, 1152. Like Charlemagne, Barbarossa (the Redbeard) aimed to rule with a firm hand. He raised Bohemia to the rank of a kingdom, and made Austria an independent duchy. He made Poland tributary to the empire. In efforts to assert the imperial authority he came into conflict with the pope repeatedly. Six times Barbarossa led an army across the Alps to straighten out the cities of Lombardy. On one of these expeditions the walls of Milan were razed, and the inhabitants were scattered among the villages. In 1176, a summer pestilence having swept away 25,000 of Barbarossa's soldiery, the cities of the Lombard League flew to arms. Aided by the countenance of the pope and by the defection of Henry the Lion, Duke of Saxony, the citizens marching on foot won the notable victory of Legnano over the feudal horsemen of Barbarossa. The emperor was glad to escape with his life, and soon afterward recognized the freedom of the Lombard towns. As soon as his hand was free, Barbarossa turned on his false vassal, Henry of Saxony, deprived him of his fiefs, and banished him from the empire.

Barbarossa was a prominent figure in the Second Crusade. In 1189 he proclaimed a universal peace in his dominions, placed the crown in charge of his son, and united with Philip II of France and Richard of England to effect the recapture of Jerusalem from Saladin. The crusaders set out with high hopes, but Barbarossa lost his life in fording a river of Syria, and the crusaders fell into jealous dispute, as set forth in Scott's Talisman.

Barbarossa was the greatest ruler of the Hohenstaufen line. He strove to exalt the imperial dignity. He fought, but he fought to secure peace and order. He was a patron of learning. He encouraged the University of Bologna--"the university of Roman law." Though he maintained a court of pomp and luxury, he put down local tyranny with a strong hand. He is one of the national heroes of Germany. One of the ancestral castles of the Hohenstaufen family sits on Kyffhauser, in the Harz Mountains. A tradition lingered long among the peasantry that Barbarossa was not dead, but that he sat in magic sleep upright on a golden throne, crown on head and scepter in hand, deep beneath the castle, and that some day, in an hour of need, he would come forth and bring his people a reign of justice and peace.

Frederick II (1712-1786), king of Prussia. He is best known in history as Frederick the Great. He was the son of Frederick William I, and the great grandson of the Great Elector. He ascended the throne in 1740. His father was very harsh with him as a boy. On one occasion a young lieutenant was put to death in his presence for having encouraged him in an attempt to run away from his father's court. He was fond of music and painting, and kept up a correspondence with the scholars and writers of the day, particularly Voltaire, whom he invited to his court. Contrary to the expectation of his friends, Frederick developed military ability of a high quality.

In some respects his career resembles that of Alexander the Great. He found Prussia a small state, but its finances were in excellent condition, and he had at his command the finest army in Europe. These advantages he owed to his stern old father. Frederick engaged in various wars with his neighbors. He robbed Maria Theresa of her Silesian provinces and exacted heavy war indemnities from Austria. He joined Russia and Austria in the division of Poland, taking the northern section for his share. In the famous Seven Years' War England supported him, chiefly with large sums of money, against the French and Austrians.

At his death it could be said of Frederick that he added 30,000 square miles to the territory of Prussia, that he left $70,-000,000 in the treasury, and an army of 200,000 of the best drilled soldiers in Europe. German scholars admit his military ability freely, but criticize him severely because he preferred the literature and manners of France to those of his native country. In his History of Frederick II, published 1858-65, Carlyle makes out that the Prussian king was one of the most heroic figures in modern history. The citizens of Berlin respect the memory of Frederick. He is their national hero. A bronze statue representing him on horseback stands in Unter den Linden in front of the imperial palace. It is considered the finest equestrian statue in existence.

Frederick was the first European sovereign to acknowledge the independence of the United States. He was not without a certain grim wit of his own. On one occasion he received a written request for assistance from a village pastor who claimed that a rival was drawing all the people to the church on the other side of the river. Frederick turned over the petition and wrote: "Tell him to go and preach on the other side of the river. That will drive them all back again."

Frederick William (1620-1688), elector of Brandenburg. He is known as the Great Elector. He was a fighter. He succeeded in securing the independence of Prussia from the Poles. He encouraged agriculture, insisted on economy, constructed several important canals, and welcomed the refugee French Huguenots to his dominions. He is recognized as the founder of the future greatness of Prussia.

Frederick William I (1688-1740), king of Prussia. He came to the throne in 1713. He had a passion for military life, yet was concerned in only one war. He had simple tastes, a high temper, and a tremendous will. He dismissed all unnecessary officers from his household, hoarded the public revenues, and built up an army. His famous Potsdam guard was made up of giants collected from the remotest parts of Europe. The building up of this guard was his greatest foible. He paid enormous sums for recruits and even resorted to kidnaping. Several of these men were over seven feet in height. They wore tall fur caps that made them seem even a foot higher.