(1577), and Italy (1578, and perhaps twice or thrice between 1550 and 1558). Beginning as a map-engraver (in 1547 he enters the Antwerp gild of St Luke as afsetter van Karten), his early career is that of a business man, and most of his journeys before 1560 are for commercial purposes (such as his yearly visits to the Frankfort fair). In 1560, however, when travelling with Gerhard Kremer (Mercator) to Trier, Lorraine and Poitiers, he seems to have been attracted, largely by Mercator’s influence, towards the career of a scientific geographer; in particular he now devoted himself, at his friend’s suggestion, to the compilation of that atlas or Theatre of the World by which he became famous. In 1564 he completed a mappemonde, which afterwards appeared in the Theatrum. He also published a map of Egypt in 1565 a plan of Britenburg Castle on the coast of Holland, and perhaps a map of Asia, before the appearance of his great work. In 1570 (May 20) was issued, by Gilles Coppens de Diest at Antwerp, Ortelius’ Theatrum Orbis Terrarum, the “first modern atlas” (of 53 maps). Three Latin editions of this (besides a Flemish, a French and a German) appeared before the end of 1572; twenty-five editions came out before Ortelius’ death in 1598; and several others were published subsequently, for the vogue continued till about 1612. Most of the maps were admittedly reproductions (a list of 87 authors is given by Ortelius himself), and many discrepancies of delineation or nomenclature occur. Errors, of course, abound, both in general conceptions and in detail; thus South America is very faulty in outline, and in Scotland the Grampians lie between the Forth and the Clyde; but, taken as a whole, this atlas with its accompanying text was a monument of rare erudition and industry. Its immediate precursor and prototype was a collection of thirty-eight maps of European lands, and of Asia, Africa, Tartary and Egypt, gathered together by the wealth and enterprise, and through the agents, of Ortelius’ friend and patron, Gilles Hooftman, lord of Cleydael and Aertselaer: most of these were printed in Rome, eight or nine only in Belgium. In 1573 Ortelius published seventeen supplementary maps under the title of Additamentum Theatri Orbis Terrarum. By this time he had formed a fine collection of coins, medals and antiques, and this produced (also in 1573, published by Philippe Galle of Antwerp) his Deorum dearumque capita . . . ex Museo Ortelii (reprinted in Gronovius, Thes. Gr. Ant. vol. vii.). In 1575 he was appointed geographer to the king of Spain, Philip II., on the recommendation of Arius Montanus, who vouched for his orthodoxy (his family, as early as 1535, had fallen under suspicion of Protestantism). In 1578 he laid the basis of a critical treatment of ancient geography by his Synonymia geographica (issued by the Plantin press at Antwerp and republished as Thesaurus geographicus in 1596). In 1584 he brought out his Nomenclator Ptolemaicus, his Parergon (a series of maps illustrating ancient history, sacred and secular), and his Itinerarium per nonnullas Galliae Belgicae partes (published at the Plantin press, and reprinted in Hegenitius, Itin. Frisio-Holl.), a record of a journey in Belgium and the Rhineland made in 1575. Among his last works were an edition of Caesar (C. I. Caesaris omnia quae extant, Leiden, Raphelingen, 1593), and the Aurei saeculi imago, sive Germanorum veterum vita (Philippe Galle, Antwerp, 1596). He also aided Welser in his edition of the Peutinger Table in 1598. In 1596 he received a presentation from Antwerp city, similar to that afterwards bestowed on Rubens; his death and burial (in St Michael’s Abbey church) in 1598 were marked by public mourning.
See Emmanuel van Meteren, Historia Belgica (Amsterdam, 1670); General Wauwermans, Histoire de l’école cartographique belge et anversoise (Antwerp, 1895), and article “Ortelius” in Biographie nationale (Belgian), vol. xvi. (Brussels, 1901); J. H. Hessels, Abrahami Ortelii epistulae (Cambridge, England, 1887); Max Rooses, Ortelius et Plantin (1880); Génard, “Généalogie d’Ortelius,” in the Bulletin de la Soc. roy. de Géog. d’Anvers (1880 and 1881). (C. R. B.)
ORTHEZ, a town of south-western France, capital of an
arrondissement in the department of Basses-Pyrénées, 25 m.
N.W. of Pau on the Southern railway to Bayonne. Pop. (1906)
town 4159; commune 6254. It is finely situated on the right
bank of the Gave de Pau which is crossed at this point by a
bridge of the 14th century, having four arches and surmounted
at its centre by a tower. Several old houses, and a church of the
12th, 14th and 15th centuries are of some interest, but the most
remarkable building is the Tour de Moncade, a pentagonal
tower of the 13th century, once the keep of a castle of the viscounts
of Béarn, and now used as a meteorological observatory.
A building of the 16th century is all that remains of the old
Calvinist university (see below). The hôtel de ville is a modern
building containing the library.
Orthez has a tribunal of first instance and is the seat of a subprefect. The spinning and weaving of cotton, especially of the fabric called toile de Béarn, flour-milling, the manufacture of paper and of leather, and the preparation of hams known as jambons de Bayonne and of other delicacies are among its industries. There are quarries of stone and marble in the neighbourhood, and the town has a thriving trade in leather, hams and lime.
At the end of the 12th century Orthez passed from the possession of the viscounts of Dax to that of the viscounts of Béarn, whose chief place of residence it became in the 13th century. Froissart records the splendour of the court of Orthez under Gaston Phoebus in the latter half of the 14th century. Jeanne d’Albret founded a Calvinist university in the town and Theodore Beza taught there for some time. An envoy sent in 1569 by Charles IX. to revive the Catholic faith had to stand a siege in Orthez which was eventually taken by assault by the Protestant captain, Gabriel, count of Montgomery. In 1684 Nicholas Foucault, intendant under Louis XIV., was more successful, as the inhabitants, ostensibly at least, renounced Protestantism, which is nevertheless still strong in the town. In 1814 the duke of Wellington defeated Marshal Soult on the hills to the north of Orthez.
ORTHOCLASE, an important rock-forming mineral belonging to the felspar group (see Felspar). It is a potash-felspar, KAlSi3O8, and crystallizes in the monoclinic system. Large and distinctly developed crystals are frequently found in the drusy cavities of granites and pegmatites. Crystals differ somewhat in habit; for example, they may be prismatic with an orthorhombic aspect (fig. 1), as in the variety adularia (from the Adular Mountains in the St Gotthard region); or tabular (fig. 2), being flattened parallel to the clino-pinacoid or plane of symmetry 𝑏 (010), as in the variety sanidine (σᾰνίς, σᾰνίδος, a board); or again the crystals may be elongated in the direction of the edge between 𝑏 and the basal plane 𝑐 (001), which is a characteristic habit of orthoclase from the granite quarries at Baveno in Italy. Twinning is frequent, and there are three well-defined twin-laws: (1) Carlsbad twins (fig. 4). Here the two individuals of the twin interpenetrate or are united parallel to the clino pinacoid: one individual may be brought into the position of the other by a rotation of 180° about the vertical crystallographic axis or prism-edge. Such twinned crystals are found at Carlsbad in Bohemia and many other places. (2) Baveno twins (fig. 5). These twins, in which 𝑛 (021) is the twin-plane, are common at Baveno. (3) Manebach twins (fig. 6). The twin-plane here is 𝑐 (001); examples of this rarer twin were first found at Manebach in Thuringia.
 Fig. 1. |
 Fig. 2. |
 Fig. 3. |
An important character of orthoclase is the cleavage. There is a direction of perfect cleavage parallel to the basal plane 𝑐, on which plane the lustre is consequently often pearly; and one less highly developed parallel to the plane of symmetry 𝑏.
