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.
THE REPRODUCTION OF THE LEARDO MAP
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.
KEY MAPS
[Illustration: Fig. 4—General key map. The numbers correspond to
those of the main center heads in the commentary on pp. 32-60.]
[Illustration: Fig. 5—Detailed key map: northeastern section. The
numbers in this and in Figs. 6-9 correspond to the Arabic numbers on
pp. 32-60.]
[Illustration: Fig. 6—Detailed key map: east-central section.]
[Illustration: Fig. 7—Detailed key map: southeastern section.]
[Illustration: Fig. 8—Detailed key map: northwestern section.]
[Illustration: Fig. 9—Detailed key map: west-central section.]
[Illustration: Fig. 10—Detailed key map: southwestern section.]
Transcriber’s Notes
—Retained publication information from the printed edition: this eBook
is public-domain in the country of publication.
—Corrected a few palpable typographical errors.
—In the Detailed Contents, broke paragraphs up so that each number
(label) is on a separate line.
—In the text versions only, text in italics is delimited by
_underscores_.