PERU (apparently from Biru, a small river on the west coast of Colombia, where Pizarro landed), a republic of the Pacific coast of South America, extending in a general N.N.W.–S.S.E. direction from lat. 3' 21' S. to about 18° S., with a sea-coast of 1240 M. and a width of 300 to 400 in., exclusive of territories in dispute. Its area in 1906, including Tacna and Arica, and other disputed territories occupied by neighbouring states, was officially estimated at 1,752,422 sq. kilometers, or 676,638 sq. m.; exclusive of these territories, the area of Peru is variously 1874, and on the 7th of October 1876 died at Munich while attending the sittings of the historical commission. The Monumenta began to appear in 1826, and at the date of his resignation 24 volumes folio (Scriptores, Leges, Diplomata) had appeared. This work for the first time made possible the existence of the modern school of scientific historians of medieval Germany. In connexion with the Monumenta Pertz also began the publication of a selection of sources in octavo form, the Scriptores rerum germanicarum in usum scholarum; among his other literary labours may be mentioned an edition of the Gesammelte Werke of Leibnitz, and a life of Stein (Leben des Ministers Freiherrn vom Stein (6 vols., 1849—1855) ; also, in an abridged form, Aus Steins Leben (2 vols.,-1856). estimated at 439,000 to 480,000 sq. in., the Gotha measurements being 1,137,000 sq. kilometers, or 439,014 sq. m. With the exception of parts of the Ecuador, Brazil and Bolivia frontiers, all the boundary lines have been disputed and referred to arbitration—those with Colombia and Ecuador to the king of Spain, and that with Bolivia to the president of Argentina, on which a decision was rendered on the 9th of July 19og. There have been misunderstandings with Ecuador in regard to some small areas in the Chira valley, but it may be assumed that the line is fixed between Santa Rosa (3° 21' S.) on the Gulf of Guayaquil, and the Chinchipe river, a tributary of the Maranon. At the junction of the Cauches with that river, that Ecuadorean line descends the Chinchipe to the Maranon, and the Peruvian ascends to a point where it is intersected by a line following the eastern Cordillera northward to the head-waters of the Caqueta, or Japuth, which forms the northern boundary down to the Brazilian frontier. This claim covers all eastern Ecuador and. a large part of south-eastern Colombia. In 1903 there were encounters between small bodies of Peruvian and Ecuadorean troops on the disputed frontier. After arbitration by the king of Spain had been agreed upon, the question was considered by two Spanish commissions, and modifications favouring Peru were recommended. These became known prematurely, and in May 1910 war was threatened between Peru and Ecuador in spite of an offer of mediation by the United States, Brazil and Argentina under the Hague Convention. From the Japura southward to the Amazon, in 40 13' 21” S., 69° 35' W., and thence up the Javary, or Yavari, to its source in 7° 8' 4" S., 73° 46' 30" W., as determined by a mixed commission, the line has been definitely settled.