387 Mo. usalatu|s: Usalaetus Mons in Province of Africa (Tunisia), Ptol. (IV, 3:18 (FA13));=Jebel Usselet near site of Hadrumetum (Müller, i, 635).
388 Mo. masarus: Mampsarus Mons in Province of Africa (Tunisia), Ptol. (l. c.).
389 Mons. bur.ea(?): Buzara Mons where Mauretania Caesariensis, the Province of Africa, and Libya Interior meet, Ptol. (IV, 2:16; IV, 3:16 (FA13));=?Jebel bu-Kahil, S of Bu-Saada, Algeria (PW, iii, 1094).
390 Mo flruxu(?): Phrouraesus Mons in Mauretania Caesariensis (Algeria), Ptol. (IV, 2:16 (FA12));=?Jurjura, SE of Algiers (Müller, i, 602).
391 Mo. garis: Garas Mons in Mauretania Caesariensis, Ptol. (l. c.).
392 Alta mons: Atlas Mons Minor on Atlantic coast of Mauretania Tingitana (Morocco), Ptol. (IV, 1:2 (FA12)); see PW, ii, 2119.—
393 A river rising SW of the Atlas Mountains and entering the western Mediterranean is shown on many fourteenth and fifteenth century maps. On CA, instead of rising in a lake with three tributaries, as Leardo represents it, the river encircles the city of Sigilmessa (=Tissimi, in oasis of Tafilet, Miller, Arab., 177), where it is entered by four tributaries from the south; a branch is also shown entering the Atlantic. On CE the river corresponds essentially to that of CA, except that the branch to the Atlantic has been made the main stream and the arm leading to the Mediterranean has been separated from that sea and converted into a doubled-channeled tributary of the main stream.
394, 395 Illeg.
396 africa(?): The Roman Province of Africa (Tunisia), Ptol. (IV, 3 (FA13)).
397 tunixi: =Tunis (Kret., Port., 679).
398 bona: =Bône (ibid., 680).
399 se ...(?): Septa of Portolan charts;=Ceuta (ibid., 683).
400 Illeg.
401 bizesta(?): ?Bichest, CA;=?Biskra.
402, 403 Illeg.
404 lucha: =“A place near Cape Lukka” or Ras el-Melh (Kret., Port., 675).
405 c. bonand|rea: Cape Bonandrea of Portolan charts;=Ras el-Hillil (ibid.).
406 Illeg.
407 bnicho(?): Bernicho of Portolan charts;=anct. Berenice, mod. Benghazi (ibid., 676).
408 Illeg.
409 licodia: =Ras el-Omja (ibid.).
410 siden: ?Sidra, CA;=island of Abu Sheifa (Bu Sceifa of Italian maps) (ibid.).
411 casero sensor: =Sensur (ibid., 677).
412 rasimabaxi: =Ras el-Makhbez (ibid.).
413 stora: =Stora (ibid., 680).
414 ancol: =Collo (ibid.).
415 zizeri: =Jijeli (ibid.).
416 buzia: =Bougie (ibid., 681).
417 titelis: =Cape Tedless (ibid.).
418 arzeia: =Arzeu (ibid., 682).
419 or.m(?): =Oran (ibid.).
420 serem: =?River Senam (ibid.).
421 om.e(?): =Honain, Cape Noe (ibid.).
422 milela: =Mellila (ibid., 683).
423 larandie: Larcudia of the Portolan charts (ibid.);=?
424 molc|mar(?): Molcemar of Portolan charts;=Alhucemas Islands (ibid.).
425 manosa: ?Manora of Portolan charts;=Mehedia (Kret., Port., 684).
426 mosa: ?Messa of Portolan charts;=?Massa (ibid., 685).
427 maran: =?
428 zemar: Zamor of Portolan charts;=Azammur (ibid., 684).
429 ninfe: Niffe of Portolan charts;=Casablanca (ibid.).
430 sofin: =Safi (ibid.).
431 [Mare] mauro(?): Unnamed on CA and CE;=Black Sea.
432 [Mare] de adriano: =Adriatic Sea.
433 Mare Me[diterr]ano.
434 Mare de Leone: =Gulf of Lions.
435 Cip[ro]: =Cyprus.
436 rodo: =Rhodes.
437 sio: =Chios (Kret., Port., 660).
438 arcipellago.
439 negropo[nte]: =Euboea.
440 ya de chrete (?): =Crete.
441 crsicha.
442 sardignia.
443 minoricha: =Minorca.
444 Maioricha: =Majorca.
445 Illeg.
446 The Guadalquivir: similar course on CA and CE.
447 f. lizer: =Loire.
448 f. stequana: =Seine.
449 f. rode|nus: =Rhône.
450 gr ... (?): =Granada.
451 Illeg.
452 span ... (?): =Spain.
453, 454 Illeg.
455 bart.|nia: =Brittany.
456 fr ... |a: =France.
457 Illeg.
458 . ugn ...(?): =?Avignon.
459 proui|..(?): =?Provence.
460 sibilia(?): =Seville.
461 lisbo|na.
462 galizia.
463 astora: =Asturias.
464 ganti|et: =?
465 malica: =Malaga.
466 sarauignia: =Salobrena (Kret., Port., 581).
467 al(?)meria.
467a carta.(?)enia: =Cartagena.
468 lacantera:= Alicante (ibid., 584-585).
469 denia.
470 toloxa: =Tolosa.
471 ualenza: =Valencia.
472 tortoxa: =Tortosa.
473 sale: =Salou.
474 taragona.
475 barzelona.
476 anpurie: =Ampurias.
477 coliuro: =Collioure
478 narbona.
479 monpolier: =Montpelier.
480 aquemorte: =Aigues Mortes.
481 guascognia: =Gascony.
482 Mare de spagnia.
483 Illeg.;=Canary Islands.
484 Ingilterra.
485 Schoz.(?): Scotia;=Scotland.
486 The Alps run due north from northern Italy.
487 f. renus: =Rhine.
488 The Elbe, unnamed (see, however, 513); similar course on CE, CA, Bianco, and other maps.
489 f. prexant: =?
490 f. sudumr(?): Sudumera, CA;=river of Sandomir, or Vistula (Hamy, 402).
491 lacus senire(?): ?Lacus Alech, CD; Lacus Nerja, CA;=?Bay of Putzig (Hamy, 400).
492-497 All illeg.
498 polana: Polonia, CA;=Poland.
499 panon|ia: =?anct. Pannonia.
500 carcou|ia(?): Cracouja, CA;=Cracow.
501 podol|.a: =Podolia.
502 austrua(?): =Austria.
503 colognia.
504 bemia: =Bohemia.
505 praga: =Prague.
506 drensna: =Dresden.
507 misen: =Meissen.
508 guse: Guise, CA;=Würtzen (Hamy, 407).
509 aquis: =?
510 mogropes: Mangobror, CA;=?Magdeburg.
511 argenimon|de: Argent Munde, CA; Tangermünde (Buchon and Tastu, 49).
512 stendar: =Stendal.
513 albia: River name made into a place name;=Elbe.
514 gara gorda(?): Garagona, CA;=Glogau (Hamy, 403).
515 schlauonia: =Sclavania, the name applied to the Slavic frontier region of Germany in the Middle Ages (Spruner-Mencke, Histor. Atlas, Mittelalter, No. 31).
516 sasonia: =Saxony.
517 ludus|maior: Ludis Magna, CA; Lundis Magna on Ptolemaic maps of the type called Scandico-Byzantine by Nordenskiöld (Periplus, 88); Bondismaguc, Con. (7; see Jiménez de la Espada 184-185);=?Lüdershagen, near Stralsund (Lelewel, ii, 65; Hamy, 400).
518 dazia: =Denmark.
519 prusia: =Prussia; see 523.
520 colbera: =Kolberg.
521 alec: Alech, CA;=Hela (Lelewel, ii, 65).
522 stetin.
523 pursia: Dupl. of 519.
524 godanse: Godansse, CA;=Danzig.
525 scheipe(?): Scorpe, CA;=?Stolp (Hamy, 400).
526 Sudana: Sudona, CA;=Sandecz (ibid., 402).
527 pante|nia: Prutenja, CA;=Königsberg on the Pregel (ibid., 401).
528 eue(?): =?
529 albig: Albing, CA;=Elbing (ibid., 402).
530 f. po.
531 Illeg.: =?Genoa.
532 Illeg.: =?Florence.
533 Illeg.: =?Rome.
534 Illeg.: =?Naples.
535 Illeg.: Vignette represents St. Mark’s and the Campanile;=Venice.
536 . . g . . (?): =?Reggio di Calabria.
537 cotron: =Cotrone (Kret., Port., 618).
538 taranto.
539 o[t]ranto.
540 brandizo: =Brindisi.
541 manfredonia.
542 guasto: =Vasto (ibid., 621).
543 ortona.
544 ancona.
545 fano.
546 pexara: =Pesaro.
547 rimano: =Rimini.
548 zexeno: =Cesenatico (ibid., 623).
549 rauena: =Ravenna.
550 ferara.
551 chioca: =Chioggia (ibid.).
The river system corresponds generally with that of CA and CE.
552 f. donoia: =Danube.
553 f. morana: =Morava.
554 f. drina: =Drin.
555 f. moree(?): =?Moldau.
556, 557, 558: Three unnamed islands in the Danube; on CA these are named: Insula de Jaurim, Insula Buda, Insula de Sermona(?).
559 bu . . .(?): =?Buda.
560 m . . l . .(?): =?
561 ongar|ia: =Hungary.
562 serui|a: =Serbia.
563 bosn|a(?): =Bosnia.
564 ulachia: =Wallachia.
565 bulga|ria.
566 dalmazi.
567 albania.
568 modon: =Methone (Kret., Port., 635).
569 coron: =Corone (ibid.).
570 salonichi.
571 filipopoli.
572 sofia.
573 andernopolli: =Adrianople.
574 garipolli: =Gallipoli.
575 pera.
576 costantinopoli.
577 Mar de alemani: =Baltic Sea.
578 ya(?) gotlandia: =Gottland.
579 Illeg.
580 The mountain system is a simplification of that shown on CE.
581 f. netur: Flū Nectir, CE; Fl. Vectur, CD;=Motala, outlet of Lake Vettern (Hamy, 387).
582 f. turontes: Turuntus Fl. in Sarmatia, Ptol. (III, 5:2 (FA9));=Dvina (Müller, i, 412).
583 in q[uesta par] te si caualca su zervi | tori et montoni et su queli fano le | loro bataie (in this region they ride on deer, bulls, and sheep, and on these they make their battles): Compare legend on CE (Kret., CE, 214).
584 In questa parte sta zente che non uide | Il sole 4 mexe de lano (in this region there are people who do not see the sun for four months of the year): Santarem (iii, 409, note 2) suggests a relation between this and a passage in Jordanis, De rebus Geticis (Monumenta Germaniae historica, Auctorum antiquissimorum, Vol. 5, Part 1, Berlin, 1882, p. 58) descriptive of the Adogitae of Scanzia, who enjoy uninterrupted sunshine for forty days and darkness for an equal period each year (see also Fridtjof Nansen, In Northern Mists, New York, 1911, i, 130-134).
585 nouega: =Norway.
586 sechamor: Scamor, CD;=Skanör (Hamy, 426).
587 scarsa: Scarsa, CD:=Skaraborg (Hamy, 383).
588 zedina: ?Andine, CD, which is possibly “nundinae,” with reference to the fairs of Skanör and Valsterbode (Hamy, 385).
589 selandia: =?Zealand, misplaced. See Nansen, Northern Mists, ii, 219.
590 suzia: Suecia, CD;=Sweden (Hamy, 383, 426).
591 stochi: Stocol, CD; Stocoll, CE;=Stockholm (Hamy, 386, 427).
592 Erma: ?Kalma, CD;=Kalmar (Hamy, 386, 427).
593 sadezeflingt(?): Suderpigel, CD; Sudechping, CE;=Söderköping (Hamy, 387, 427).
594 saglat: Asillang, CE; Assingland on fourteenth century map in Museo Borbonico, Naples (Hamy, 427);=?
595 roder|in: Roderin, CD; CE;=Roden, ancient name for the east coast of Sweden;=Rosladen (Hamy, 387, 427).
596 Mo. ripei: Dupl. of 2.
597 Leardo’s unnamed river entering E extremity of Baltic is called Flum Nu on CD; Flum de Mi, CE;=Volkhof and Neva, confused (Hamy, 390).
598 f. axiazes: Axiaces Fl. of Sarmatia Europae, Ptol. (III, 5:18 (FA9)).
599 f. turllo: Kretschmer (Port., 642) records Flumen Turle only on an anonymous fifteenth century map in the Museum für Meereskunde, Berlin (ibid., pp. 133-135);=Dniester (ibid., 642).
600 zimachia Inferior: ?corruption of Sarmatia, Ptol. (passim (FA9)). See also 12.
601 rosia: =Russia.
602 Lordo, applying to a group of tents;=the Golden Horde of Tatars (Hallb., 318-319).
603 nogard|ia: Nogorado, CD; Nogorodo, CE;=Novgorod (Hamy, 390).
604 alana: Allania, CA;=the Alans (Hallb., 13-14).
605 albana: Albania, NW of Caspian Sea, Ptol. (V, 12 (FA18)); see Hallb., 14-15;=Shirvan and Daghestan (Besnier, 29).
606 br . . ica(?): Branchicha, CA; Brancica, Piz.;=Briansk (Hamy, 392).
607 brachi|at: ?Dupl. of 606.
608 bthnia: =?Bothnia.
609 rossia: Dupl. of 601.
610 transil|uana: =Transylvania, misplaced.
611 gotia: =“A small stretch of land between the Yaila Range and the coast, in the hands of the Genoese after the fourteenth century” (Kret., Port., 643); see also Yule, Polo, ii, 492.
612 soldaia: =Sudak, important trading post in Genoese hands after 1365 (ibid., 644).
613 gafa: =Kafa, Feodosia (ibid.).
614 soronti(?): =?
615 uospe|ro: =Kerch (ibid.).
616 piaha(?): =?Pinsk.
617 letefa|n paga|n: Litefanie Pagans, CA;=Lithuania (Hamy, 398-399).
618 perana: Perum, CA; CE=Murom (Hamy, 394).
619 DIXERTO DEXABITADO PER FREDO (desert uninhabited because of cold): See 305.
The publications listed here are those to which frequent reference only is made in the Notes and Appendix. The abbreviations there employed precede each reference.
Besnier: Maurice Besnier, Lexique de géographie ancienne, Paris, 1914.
Buchon and Tastu: J. A. C. Buchon and J. Tastu, Notice d’un atlas en langue catalane, manuscrit de l’an 1375, conservé parmi les manuscrits de la Bibliothèque Royale sous le No 6816, fonds ancien, in-folio maximo, in Notices et extraits de manuscrits de la Bibliothèque du Roi et autres bibliothèques, Vol. 14, Paris, 1841, pp. 1-152.
Only complete transcription and commentary on the Catalan Atlas. See CA.
CA: Catalan Atlas (i. e. map divided into six parchment sheets) of 1375; sometimes called Catalan Atlas of Charles V, to whose library it belonged. Facsimile in: Choix de documents géographiques conservés à la Bibliothèque Nationale, Paris, 1883.
See Kret., Port., pp. 123-124; Buchon and Tastu; Cordier, CA.
CD: Map of Angellino Dulcert, 1339. See E. T. Hamy, La mappemonde d’Angelino Dulcert, de Majorque (1339), 2nd edition, Paris, 1903 (with photographic reproduction).
See Kret., Port., pp. 118-119.
CE: Catalan map of fifteenth century in Biblioteca Estense, Modena. Colored reproduction accompanying Konrad Kretschmer, Die Katalanische Weltkarte der Biblioteca Estense zu Modena, in Zeitschr. Gesell. für Erdkunde zu Berlin, Vol. 32, 1897, pp. 65-111, 191-218 (=Kret., CE). Photographic reproduction in F. L. Pullé, Studi italiani di filologia indo-iranica, Vol. 5, Atlas, Florence, 1905.
Con.: Libro del conosçimiento de todos los reynos y tierras ... escrito por un franciscano español à mediados del siglo XIV. Our references are to the pages of Sir Clements Markham’s translation and edition (of Jiménez de la Espada’s edition, q. v.) entitled Book of the Knowledge of all the Kingdoms...., Hakluyt Society [Publs.], Ser. 2, Vol. 29, London, 1912.
Cordier, CA: Henri Cordier, L’Extrême-Orient dans l’atlas catalan de Charles V, Roi de France, in Bulletin de géographie historique et descriptive, Vol. 10, 1895, pp. 19-64.
Cordier, Ser M. P.: Henri Cordier, Ser Marco Polo: Notes and Addenda to Sir Henry Yule’s Edition, Containing the Results of Recent Research and Discovery, London and New York, 1920.
FA: See Ptolemy.
Fischer: Theobold Fischer, Sammlung mittelalterlicher Welt- und Seekarten italienischen Ursprungs und aus italienischen Bibliotheken und Archiven herausgegeben und erläutert, Venice, 1886.
Text accompanying Raccolta.
Gerini: G. E. Gerini, Researches on Ptolemy’s Geography of Eastern Asia (Further India and Indo-Malay Archipelago), constituting Asiatic Society Monographs No. 1, London, 1909.
Hallb: Ivar Hallberg, L’Extrême Orient dans la littérature et la cartographie de l’Occident des XIIIe, XIVe, et XVe siècles: étude sur l’histoire de la géographie, Göteborg, 1906.
Alphabetical list of place names throughout Asia as a whole (not merely the Far East) with variant forms, references to the sources, and identifications.
Hamy: E. T. Hamy, Les origines de la cartographie de l’Europe septentrionale, in Bulletin de géographie historique et descriptive, Vol. 3, 1888, pp. 333-432.
Jiménez de la Espada: Márcos Jiménez de la Espada, editor, Libro del conosçimiento de todos los reynos y tierras ... escrito por un franciscano español á mediados del siglo XIV, Madrid, 1877.
See also Con.
Kret., CE: See CE.
Kret., Port.: Konrad Kretschmer, Die italienischen Portolane des Mittelalters, ein Beitrag zur Geschichte der Kartographie und Nautik, constituting Veröffentlichungen, Instit. für Meereskunde und Geographisches Instit. an der Universität Berlin, No. 13, Berlin, 1909.
This fundamental study includes a descriptive list of the principal portolan charts and a list of the names shown on them along the coasts of the Mediterranean and Atlantic, with identifications with modern names.
La R.: Charles de La Roncière, La découverte de l’Afrique au moyen âge, cartographes et explorateurs, Vols. 1 and 2, Cairo, 1925.
Lelewel: Joachim Lelewel, Géographie du moyen age, 5 vols. and atlas, Brussels, 1852-1857.
Mauro: Fra Mauro’s map of the world, c. 1458, in Doge’s Palace, Venice. Much reduced photographic reproduction in Raccolta, No. 15; copy in Santarem, Atlas.
See Zurla; Kret., Port., p. 140.
Miller, Arab.: Konrad Miller, Mappae arabicae: arabische Welt- und Länderkarten des 9.-13. Jahrhunderts, 6 vols. (of which Vols. 3, 4, and 5 have not yet appeared), Stuttgart, 1926-1927.
Miller, Mappaemundi: Konrad Miller, Mappaemundi: die ältesten Weltkarten, 6 vols., Stuttgart, 1895-1898.
Müller: Carl Müller, editor, Claudii Ptolemaei geographia, Vol. 1, Parts 1 and 2, and Atlas, Paris 1883, 1901. Covers Bks. I-V only. See Ptol.
Nordenskiöld, Periplus: A. E. Nordenskiöld, Periplus, an Essay on the Early History of Charts and Sailing-Directions, transl. by F. A. Bather, Stockholm, 1897.
Piz.: Francesco Pizigano’s map, 1367, in National Library, Parma. Copy in [E.-F.] Jomard, Les monuments de la géographie, ou recueil d’anciennes cartes.... Paris, [1862].
See Kret., Port., pp. 121-122.
Polo: Marco Polo, The Book of Ser Marco Polo the Venetian Concerning the Kingdoms and Marvels of the East, translated and edited with notes by Sir Henry Yule, 3rd edition revised by Henri Cordier, 2 vols., London, 1903.
Except where otherwise indicated all references are to volumes and pages of this edition.
Ptol.: Ptolemy (Claudius Ptolemaeus), Geographia, edited by C. F. A. Nobbe, 3 vols., Leipzig, Vol. 1, 1898; Vol. 2, 1913; Vol. 3, n. d.
References are to book, chapter, and section of this edition. References indicated by FA are to the plates on which reproductions from the Rome, 1490, edition are given in A. E. Nördenskiöld, Facsimile-Atlas to the Early History of Cartography with Reproductions of the Most Important Maps Printed in the XV and XVI Centuries, translated from the Swedish Original by J. A. Ekelöf and C. R. Markham, Stockholm, 1889.
Pullé, Vat.: See Vat.
PW: Paulys Real-encyclopädie der classischen Altertumswissenschaft, new edition begun by Georg Wissowa. 15 vols, and 4 supplements have appeared (1927), Stuttgart, 1894-.
Raccolta: Raccolta di mappamondi e carte nautiche del XIII al XVI secolo, (H. F. and M. Münster, succeeded by) Ferd. Ongania, Venice, (1869?), 1881. (Series of photographic facsimiles of 17 maps, also known as Ongania Collection. See Fischer.)
Rainaud: Armand Rainaud, Le continent austral: hypothèses et découvertes, Paris, 1893.
Santarem: Le Vicomte de Santarem, Essai sur l’histoire de la cosmographie et de la cartographie pendant le moyen-age...., 3 vols. and atlas, Paris, 1849-1852.
Spruner-Menke: K. von Spruner and Th. Menke, Hand-atlas für die Geschichte des Mittelalters und der neueren Zeit (third edition of Spruner’s atlas revised by Menke), Gotha, 1880.
Vat.: Map in Vatican Library, fondo Museo Borgiano, No. V. Photographic reproduction with commentary in: F. L. Pullé, Una carta itineraria del secolo XV [Vaticana Borgiana], constituting Studi italiani di filologia indo-iranica, Vol. 5, La cartografia antica dell’ India, Part 2, Appendix 4, Florence, 1905 (=Pullé, Vat.).
Vilad.: Map of Mecia de Viladestes, 1413. Colored reproduction of African portion as frontispiece of La R., Vol. 1.
See Kret., Port., p. 126.
Vivien de St. Martin: [Louis] Vivien de St. Martin, Le nord de l’Afrique dans l’antiquité grecque et romaine: étude historique et géographique, Paris, 1863.
Wright, Lore: J. K. Wright, The Geographical Lore of the Time of the Crusades: a Study in the History of Medieval Science and Tradition in Western Europe, constituting American Geographical Society Research Series No. 15, New York, 1925.
Yule, Cath.: Sir Henry Yule, Cathay and the Way Thither, 2nd edit., edited by Henri Cordier, 4 vols., Hakluyt Society [Publs.], Ser. 2, Vols. 33, 37, 38, 41, London, 1913-1916.
Yule, Polo: See Polo.
Zurla: Placido Zurla, Il mappamondo di Fra Mauro Camaldolese, Venice, 1806.
By A. B. Hoen
A. Hoen & Company, Baltimore, Md.
[One of the first things usually asked in regard to the reproduction or facsimile of an old map is: “How was it made?” To answer this question and to give some idea of the difficult technical problems involved, Mr. Hoen, under whose direction the Society’s reproduction of the Leardo Map was made, has been kind enough to furnish the following note.—J. K. W.]
The Leardo Map is painted on parchment. Some of the colors have faded, and others here and there have separated from the skin, leaving blanks in the painting. The latter defects are especially noticeable in the yellow zones encircling the map proper. To avoid the injection of the personal element into the reproduction, no attempt was made to restore the missing letters or symbols. It is further to be noted that in cases of partial legibility the very palest parts of the faded manuscript may have failed to register in the reproduction, although great care was bestowed on this part of the work.
As a first step in the reproduction of the map, color separation negatives were made on photographic plates sensitized for all the colors. By interposing proper light filters and by making separate exposures for each color, negatives giving red, yellow or green, and blue or purple values were made, together with a fourth negative giving neutral tones—black and grays.
As the last negative comprehends almost the entire base of the map, special attention was devoted to its conversion into a printing plate. The process employed is known in Germany as “Albertype” or “Lichtdruck,” in England as “collotype,” and in America as “heliotype” or “photogelatin.” Of these names, “collotype” seems to be the most fitting. Briefly, this process consists of sensitizing a gelatin film with a chromic salt and exposing it to light under a negative. In proportion to the amount of light passing the negative there will be a reaction in the chromated gelatin. In this reaction the gelatin loses its power of absorbing water and takes on the opposite property of holding “non-watery” substances, such as printing ink. The action of the light is a graded one, varying from full effect under the clear parts of the negative to nil under the very dense parts. A similar gradation in ink-retaining powers is acquired by the exposed gelatin film. Thus, where the light exerts full effect the gelatin will be completely hardened and will hold the ink in its greatest intensity (solid); the parts which receive less light or none at all will hold the ink in attenuated quantity. The lights and shades of the monochrome picture are thus reproduced.
In order that the film may exercise this selective power of taking on or rejecting ink it is necessary that the unaltered parts be kept moist. Therefore, after exposure under the negative, the film is washed to free the gelatin of the unused chromates. While still moist it is rolled with a roller carrying printing ink. This roller will discharge its ink on the hardened parts of the film in proportion to the amount of light that each part has received through the negative. If a sheet of paper is then pressed on the inked film it will lift the ink and the resulting impression will be of the same character as the base color of the Leardo Map.
It is of interest to note that as the light-affected and hardened surface of the film accommodates itself to the unaffected underlying gelatin (as the latter swells in washing) it breaks up into a net of lines. This reticulation is barely perceptible in the high lights of the picture but gradually increases in strength until the mesh fuses into the solid color of the deepest shades.
It will now be apparent that the feasibility of printing these colloid plates hinges on the fact that the graded ink-attracting mesh is separated by inversely graded ink-repelling, interstitial, unaltered, and moist gelatin.
Its mesh not being apparent to the unaided eye, the collotype approaches the fidelity of a true photograph in the rendering of details. For this reason, the collotype process has been selected as best suited for the reproduction of the Leardo base.
The coloring of the map was done by overprinting, in lithography, as many colors as were deemed necessary to convey a fair idea of the original. Lithographic plates were made from the color separation negatives mentioned above. The principles underlying the lithographic process are, broadly, similar to those described for gelatin printing, the essential elements in the process being a water-absorbing ground mass (limestone) in place of the gelatin and a water-repelling and ink-attracting surface affection similar to that created by the action of light on the chromated gelatin film.
Lithographic stone is an amorphous carbonate of lime of fine, close texture. It has an affinity for water—that is, it is easily kept damp. This affinity may be destroyed by changing the carbonate of lime to some water-resisting salt, such as the oleate, or by adding to the surface of the stone a film having the same power. Both of these methods were utilized in making the color plates of the Leardo Map.
A number of lithographic stones were properly surfaced and this surface covered with very thin, light-sensitive, colloid films. The color separation negatives were exposed over these sensitive films and the resulting photographs on stone gave the red, yellow, blue, and other values of the original as they had been analyzed by the light filters.
No color separation process, however, can eliminate from the areal coloring the black and grays of the base. Similarly, the colors themselves absorb a certain amount of white light so that the effect of the areal coloring is also felt in the monochrome reproduction of the base map (e. g., gray lettering is lost in heavily colored areas). For this reason, it is necessary to correct by hand the unnatural effect produced by the overprinting of all the color plates in the darker portions of the picture. Lithography is best suited for the control of these difficulties, and for this reason the color plates were made on stone.
The mechanical printing of the edition from gelatin or stone embraces three essential operations: (1) moistening the plate by damping rollers; (2) inking the plate by inking rollers; (3) pressing of suitable paper on the inked plate. After the base is printed, the base plate is taken from the press, another plate, carrying one of the map colors, is placed in position, and the proper color put on the inking rollers. The printing of the second color is then done as was that of the base. Similar changes of the printing plates and colored inks follow in order for each of the colors which make up the complete map.
Eight color printings in addition to the base color were found necessary for the proper rendering of the Leardo painting. One of these, a light gray-buff, covers the area of the parchment and serves to bring it out from the white paper background.
In selecting a suitable paper for this reproduction, certain qualities had to be considered. Among these were good printing surface, durability, and as much strength as could be had along with the above essentials. A chart plate paper of high rag content was made especially for the work.