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Albumen Process

Photographic printing process devised in France in 1855, which became very popular and replaced the salted paper process. Ammonium chloride was added after the eggwhite had been carefully separated from the yolk. The mixture was whipped into a foam and then left to stand for several hours. The liquid part left on the bottom of the container was left to ferment, was then employed in the albumen printing paper. The paper used was very thin and water-resistant. The sheets were left to "float" on the surface of the liquid and then left to dry. After this treatment, the paper could be preserved for a long time, until it was used when it had to be sensitised with an acid solution of silver nitrate. It was then used for printing after exposure to light, then was washed, gold-toned, fixed and washed again. Albumen contact printing had a higher gloss than the paper printing which was opaque.
The novelty of this process was that the albumen layer on which the image resides was separated from the paper fibre: this was the first attempt to separate the image from the support. This process was used for about 30-40 years and only by 1880-1890 was it starting to be replaced by more practical materials.

Aquatint

Indirect copperplate technique similar to etching as far as the action of acid is concerned but different with regard to the preparation of the plate. The plate is covered with a layer made out of grains of colophony (Greek pitch), or bitumen, sugar and salt, which is made to adhere to the metal through the application of heat. After having removed the varnish with a sharp point in order to obtain the drawing, the plate is immersed in the acid. The liquid penetrates into the grooves among the grains and, coming into contact with the metal, eats into it and produces a spongy image. During the printing it is possible to obtain subtle tones similar to watercolour effects.

Biffatura (Striking out)

Scratches traced on the matrix to avoid the printing of further copies.

Book binding

The technique for covering a book. The typical binding of the first book consisted of wooden boards covered with leather and blind stamped. Between the 15th and 16th century a new trend of book binding became widespread, called "aldina" (since it was invented by Aldo Manuzio), consisting of cardboard covered with calfskin instead of wood. It was decorated with very simple motifs obtained by pressing small iron instruments shaped like small leaves and roses and was particularly suitable for the new octavo size Manuzio himself had launched on the book market. Among the most famous kinds of book binding were: "caisson", "medallion", "farnese", "fanfare", "Grolier", "fan", "lace", "board binding", "neoclassical", "romantic", "liberty" and so on.

Burin/Graver

Steel instrument, employed by the engraver, with a triangular point and sharp edges. It can engrave a metal plate (copper, zinc, steel) removing the metal and leaving a clean cut. This term (burin) also indicates the direct copperplate technique which consists in the engraving of a plate with this instrument. During the inking phase, the plate receives the same treatment as an etched plate. For printing, a copperplate press is used. Burin engraving is the oldest copperplate technique: it was already being used in the first half of the 15th century but, around the first half of the following century, when etching techniques became more popular, it was no longer used.

Calotype

Photographic process invented in England in 1839, by the scientist William Henry Fox Talbot. The calotype (which in Greek means "good prototype") makes it possible to make several positive copies of a picture from the same negative, unlike the contemporary dagherrotype which did one at a time. The calotype, an ancestor of the modern negative, was a transparent sheet of light-sensitive paper, first immersed in a saline solution then in silver nitrate. After exposure in the camera, the calotype was developed, fixed - to prevent the silver salts from further alteration - washed and then sprinkled with wax in order to make the fibres of the paper more transparent and to facilitate printing on salted paper.

Cinquecentina

Edition of books printed in the 16th century.

Collodion

A photographic procedure invented in England in 1851 by the sculptor and amateur photographer Frederick Scott Archer to overcome the problems arising from the use of the paper utilised as negatives in the earlier photographic experiments (calotype). F.S. Archer replaced the paper with a glass plate covered with a thin layer of collodium, a viscous solution of nitrocellulose in alcohol and ether combined with silver salts. the plate was then bathed in a solution of silver nitrate which reacted with the salts in the collodion layer thereby forming a light-sensitive film. Once it was sensitised, the plate was put in the camera while still wet. It had to be exposed and developed as quickly as possible, before the collodion began to dry out. The technique was thus called the "wet-plate" method. The picture was then fixed in a solution of sodium thiosulphate. The negative thereby obtained was more fragile that a paper negative, but it speeded up the printing process and reproduced the picture more accurately.

Colophon

Or signature is the formula ending every book printed in the 14th century and also in the first part of the 15th. Afterwards, the frontespiece came into use. Often printed in red, it normally contains the name of the typographer, the place and date of printing often including the day and month, at times including the name of the patron publisher, the address of the workshop and the printer's mark.

Copper-plate Printing

This term indicates the techniques of tracing grooves on a plate. These techniques can be direct (burin, drypoint, etc.) or indirect (etching, aquatint, etc.). In direct engraving, the metallic plate is directly scratched with a burin or a point, while in indirect engraving, the etching of the plate takes place chemically, thanks to the erosive action of nitric acid. The copper-plate press is used for printing.

Copperplate press

It is made by a roller exerting strong pressure on the sheet to be printed, which adheres to an inked plate. That pressure drives the paper into the inked grooves of the plate so that the ink is transferred onto the sheet.

Copy

Each individual print from a printing.

Dagherrotype

A procedure perfected by Louis Daguerre in Paris in 1839 that marks the birth of photography. Daguerre's invention made it possible to obtain faithful reproductions using chemicals, a dark room and light with no need for drawing, which had up to now been the only means of reproducing real-life subjects. A silver-plated copper plate was used, sensitised with iodine vapours and developed in mercury vapour. It was mounted under glass to protect the delicate picture. The dagherrotype left a positive image directly on the plate, and this could not be reproduced. Given the limitation that only one copy was possible, the dagherrotype soon gave way to the modern negative photograph, the calotype.

Designer

Creator of the drawing that the engraver then puts on the matrix. The terms most commonly used in connection with the designer are: delineavit (de. or delin.), designavit (design.), descripsit.

Drypoint

Copperplate printing technique in which the plate is cut with steel points which create so-called "whiskers" on the groove's edges. In the printing phase, these very small raised elements create the effect of softness and vagueness in the mark.

Edge

Surface formed by the sheets of a closed volume (upper or top edge, front or concave edge, lower or foot edge). It can be coloured (with a single tint), painted (if decorated with single-coloured or many-coloured patterns), gilt (with the application of a gold leaf), embossed (if hot-carved with a relief effect), carved (if cold-carved), marbled (if mottled with variegated streaks), sprayed (if the colour is spread in little spots), etc.

Edition

The entire number of copies of a book printed at one time. In modern graphics the copies of each edition are countermarked by a double numbering showing both the serial number of each copy and the total of the copies printed.

Engraver

Artist who transposes the drawing, executed by the drawer, onto the matrix, etching the counterpart - the person is designated with the terms incidit (inc.), incidebat, sculpebat (sc. or sculp.) in the case of etching; fecit or faciebat (f. or fac.) if the engraver was also inventor and drawer.

Engraving

Various types of engraving exist:
Intaglio engraving: indicates the procedure in which the grooves of the matrix are inked. It can be performed directly by using a burin, drypoint, etc.) or indirectly through the corrosive action of acid (aquafortis, acquatint, etc.)
Relief engraving: indicates those procedures (xylography, linoleography, relief acquafortis, etc.) in which the relief printing technique is used, since the ink is transferred to the paper by the raised surfaces of the matrix, that is the part not engraved.
Planographic engraving: indicates those procedures (lithography, zincography, etc.) in which the matrix is not engraved and printing is performed using a lithographic press.
Two categories of engraving existed up to the end of the 18th century, invention engraving and reproduction engraving depending on whether the subject portrayed was invented by the engraver or copied from a preceding work by a different author.

Etching (Aquafortis)

Indirect copperplate technique through which the grooves on the copper plate are cut by the action of nitric acid on the metal (hence the name aqua fortis). The plate is first covered with an acid-proof varnish made of wax, bitumen and mastic. The lines are traced on the reverse using a sharp steel point which scratches the layer of varnish. The etching plate is then immersed in the acid, which attacks the metal in the unvarnished areas, for a period of time which depends on the depth of the engraving required. After the acid bath, the rest of the varnish is removed and the plate is then ready to be inked.
For the print a copperplate press is used.
In the 17th century etching became the favourite technique of the painters-engravers because it was easier than the burin, since it was used on a soft surface, and also because it better rendered pictorial and light effects.

Ex libris (bookplate)

A printed or engraved label in a book that indicates the owner or the origin of the volume. It may or may not include the motto of the owner. By extension any form, usually a hand-written note, that indicates the owner of a volume (a person, a library, institution, etc.).

Folio

The format of a sheet of paper obtained by folding the page in two on a parallel with the short side to make up two leaves, with the vertical wires and the watermark in the centre of one of the leaves.

Format

The word designates how the sheets of paper comprising the volume have been folded. It depends on the original size of the paper and the number of folds. The most common formats are: in-folio, in-quarto, in-ottavo, in-sixteenths, etc.

Frontespiece

A page normally at the beginning of a publication supplying all the information about the contents of the book (author, title, typographical notes). As the art of printing progressed, the typographical mark of a rule, first xylographic then copperplate (within which the printed text was placed), the picture or the motto of the author or person to whom the volume was dedicated were added.

Half tone

It is a copperplate printing technique that uses the negatives, because the metal slab prints in black, the engraver's task being to obtain the half tones and white from the black. The slab is prepared with a steel comb, called a "berceau" or "half moon", which is passed over it in every direction to obtain a uniform graining. In order for the drawing to appear, the engraver scratches or tones down the marks previously obtained. During the printing phase, these parts will appear clearly.

Impressione

Operazione eseguita a mano o con torchi o macchinari al fine di trasferire sulla carta l'immagine tratta dalla matrice inchiostrata.

Imprint

Mark left on the paper by the strong pressure of the press on the matrix in the copperplate printing phase.

Incunabula

Term (in cuna = inside the cradle) used for the first books printed, generally for those printed up to the 15th century.

Initial letter

The initial letter is the letter of the alphabet stressing the parts in which a text is divided; it can signal the beginning of a book, a chapter or simply a paragraph. It comes from the manuscripts in which the initial letters were miniatures. It can be xylographic or copperplate, rubricated (coloured in red), epigraphic (capital letter imitating the Roman capital letters), watermarked (decorated with fine designs), figured (containing objects, characters or animals), historiated (containing narrative scenes), speaking (illustrated by a figure whose name starts with the same letter of the alphabet).

Inking

The matrix is covered with ink prior to printing. In copperplate matrices the ink is spread on the entire surface and then gradually eliminated from the areas that have not been engraved. In xylographic printing, it is spread only over the raised areas.

Inventor

The author of the subject depicted in the engraving. The terms inventor, invenit (inv.), pinxit were used to indicate this person.

Linoleography

Modern variation on xylography, using a linoleum matrix, in which the parts in relief are inked.

Lithography

Or zincography. Printing technique on a table, in which the matrix, originally stone, then later, zinc, is drawn with very oily inks. During the printing phase, which is carried out with a flat machine and not with a printing press, the ink only adheres to the oily parts. It is a simple and quick method, in which the artist paints or draws as if on a sheet. It was perfected at the end of the 18th century in Munich and became widespread throughout Europe.

Matrix

Surface of various materials (wood, copper, zinc, stone, steel) on which the image is traced, which is then printed by inking and putting pressure on the sheet. It is a plate for intaglio engravings, or a wooden board for relief engravings.

Motto

A figure, with or without a written motto to explain the meaning, that expresses a thought allegorically. It is chosen by a person, family, state or body as a distinguishing sign so as to become an emblem.

Movable-type printing

A relief-printing technique invented in the West by the German Johann Gutenberg around 1440 then perfected in approximately a decade. The three essential elements were: moveable characters made from molten metal, oily ink and the press.
The type was made following this procedure: for every letter or typographical mark a hard metal "punch" was made. This was a steel bar at the end of which the character was etched. The punch was driven into a "matrix" of softer metal where the sunken impression was obtained. At this point the matrix was put in a mould thereby making possible the casting of as many metal, tin, or lead characters as needed for the desired printing. The typographical mark stood out in relief as had been the case for the punch. The problem was to locate metals and alloys hard enough not to wear out after just a few matrices had been made. The matrices were not to wear out too quickly, the characters had to be easily inked and were likewise not to deteriorate too quickly with use. The page was then composed. The procedure was as follows: the required characters were taken out of the various cases and put into a small elongated receptacle making up one line, going in the opposite direction from the final printed result. The rows were placed between two spacers which kept them separate. They were then grouped onto a page and the pages jointed in a form. An ink-pad was used to ink the form, the sheet was placed above the characters and the press printed the characters onto the paper.

Niello

An ancient technique to decorate precious metals in which the lines carved on the surface were filled with a very black substance, called nigellum, obtained by melting lead, copper and sulphur. The term also refers to the test the goldsmith made on paper to verify the carving work: before pouring the nigellum into the grooves, the printer filled them with a black substance (oil and a very intense black) and then pressed the object onto the sheet. This technique played a very important role in the success of metal engraving in the second half of the 15th century.

Octavo

The format of a sheet of paper obtained by folding it three times, the first one parallel to the short side, the second one parallel to the long side and the third one parallel to the short side to form an eight-page booklet, with vertical lines and the watermark on the top inside corner along the pamphlet stitching.

Paper

The art of manufacturing paper was discovered by the Chinese in the 2nd century A.D. It was introduced in Central Asia and Persia by the Arabs, who learnt the technique from the Chinese. The first paper factory was built in Samarcand, then, other factories were built in Baghdad, Damascus, Armenia, Persia and Egypt. It came to Mediterranean countries, first spreading in Spain, to Jativa, near Valencia, during the 12th century, and then to Italy: Bologna, Amalfi and Friuli, but especially Fabriano, in the Ancona region. Fabriano became the most famous centre of paper production also because of the improvements made in manufacturing techniques.
The raw materials used to manufacture paper were linen rags, hemp and cotton. First, they were washed, then separated according to quality then left to macerate in water. They were then shredded and taken to the mill. Here they were treated with multiple-mesh pestles. The mill shaft had wooden projections that drove meshes and pestles moving in wooden basins. The basins contained the rags soaked in soapy water, until they were turned into pulp, then transferred to vats or "tuns". A wooden framework in the vats had a series of small bronze rods. These were a few millimetres apart and kept in place by small copper or bronze wires. The papermakers of Fabriano also invented watermarks. The framework was repeatedly shaken so that the pulp would deposit in a uniform fashion. A sheet was thereby obtained that could be spread out to dry on wool felt. Several sheets with felt between them were passed through a press to eliminate the water and make it possible to separate them. A great deal of water was needed for all these operations, around two thousand litres (ca. 1700 quarts) for every kilogram (ca. 2 pounds) of paper. In order to make the paper fit for writing, it had to be waterproofed with glue coming from hide-tanning waste substances. It was then smoothed out with a stone to eliminate all the imperfections.
Certain particular features distinguish the paper used for art printing: the surface must be homogeneous, porous, sufficiently absorbent, and suitable for printing on by inked plates. In past centuries "manifold" and "Japanese" paper (more compact and free of points). Nowadays, handmade paper is still the best type for art printing. It is made by pulping rags, and ha edges which are generally fringed.

Paper (Salted)

This was what the calotype was printed on. Printing took place via contact, by means of a printing frame, between the paper sensitized with a solution of silver nitrate and the negative. The paper was then exposed to light until the desired degree of darkness was reached. In this phase, the picture acquired a reddish tone; after being fixed in a solution of sodium thiosulphate it took on a brownish tone, then a colder hue tending towards purple or violet if gilded. The colour of the photographs obtained was quite variable depending on the paper used or the salt mixture. The calotype-salted paper procedure was the one mainly used in the years between 1840 and 1860. It was then replaced by albumin printing.

Photoengravure

Copperplate printing by means of a metal plate photomechanically engraved.

Press

Printing machine used to impress matrices. It can be copperplate (used to print sunken engravings), printing (for relief engravings) or lithographic (to print matrices obtained through lithographic techniques).

<strong>Copperplate printing</strong>:
This consists of a roller exerting great pressure on a page to be printed which is placed in contact with the inked plate. The pressure pushes the paper into the inked grooves of the place in such a way that the ink transfers to the page.

<strong>Printing press</strong>:
The first printing presses, used from the 15th century following the introduction of movable-type printing, were basically mere presses. They were formed by a perpetual-screw trunk controlled by a flywheel and two plates: a lower one, on which the printing composition or the xylographic matrix were placed, and an upper movable one, which exerted the pressure needed to print through the action of the screw. Two workmen were needed to operate the press: one inked the matrix using two mallets covered with leather, while the other prepared the sheet, exerted the pressure through the action of the screw and then removed the sheet printed. All the first printing presses were made of wood, and were later replaced by a marble or granite plate, as the wooden surface on which the matrix was placed wore out quickly. With the first printing presses it was possible to print 500 copies in 12 hours; during the 16th century the press was adjusted and improved so that workmen could print one sheet every 20 seconds. The structure of the press remained almost unchanged until the end of the 18th century. Nowadays plano-cylindric presses are used, made of a metal printing surface, on which a rubber-covered roller with a sheet clinging to it runs.
Lithographic press:
The stone or the zinc sheet on which the page is pressed are mounted on a sliding plate. the lithographic technique has partly replaced the more laborious and expensive phases of copperplate printing.

Privilege

Authorization, for a limited number of years, to print and commercialise a certain work. It is granted by the ecclesiastical or civil authorities to the printer or publisher.

Prova d'artista

Esemplare che l'artista stampa precedentemente e in aggiunta alla tiratura definitiva.

Publisher

At the beginning of the age of printing the function of publisher, meaning the one who procured the publication of unpublished works considered important for the history of culture, who also took care of the drafting of the text and took a critical approach was performed by the typographer himself (Manunzio, Giolito, Giunta, Elzevier, Estienne). This function gradually took on the meaning of the one who was responsible for the publication in its entirety. As far as the printing of works of art is concerned, it is the person or body which has seen to the publication of the print: the publisher's name can be accompanied by expressions such as: appresso, apud, chez, divulgavit, excudit, ex officina; when the publisher was also the printer the terms ex typis or ex formis were used.

Quarto

Format of a sheet of paper obtained by folding the sheet twice, the first parallel to the short side and the second parallel to the long one to make up a booklet of 4 pages, with the horizontal wires and the watermark in a central position along the seam line.

Rule

One of the decorative elements of the pages of a book or a print. It can be xylographic or copperplate and take specific names depending on what is portrayed: it can be architectonic (capitals, columns, niches, statues, portals with curls or festoons, garlands, medallions, masks, dolphins, tritons, sirens or cupids), illustrated with historical scenes (brief narrative scenes), manieristic (festoons, curls, volutes, bunches of fruit, scrolls, plaques, drapery, cornucopias, masks, putti, shells, volutes, caryatids), typographical (thin borders with small flower patterns, bands and double bands), floral (grotesques, wreaths of fruit or leaves, leaf curls and flowers with birds, intertwined acanthus leaves, or vine shoots).

Run

Corresponds to the number of copies printed together. In modern printing, the copies from each run are double-numbered with the serial number and total number of copies printed.

Serigraph (Screen Print)

A printing technique originating in China. The matrix is made of silk or nylon stretched over a frame. Areas of the fabric are covered with paints or waterproof material. The ink is applied to the areas free of paints or glues.

Silver-bromide gelatin

The use of the silver-bromide plate - also referred to as a dry plate to distinguish it from the wet collodion - was introduced around 1880. The negative was obtained by extending a layer of gelatin containing a silver salt - silver bromide - on a glass plate. This mixture formed a photoemulsion substance similar to what is used in modern films. These plates could be stored until they were used. The greater sensitivity of these chemicals helped overcome the difficulties involved in taking pictures. The greater simplicity, the sharpness of details and possibility to take a picture instantaneously made photograph accessible not just to professionals. The following century saw the transition from glass to celluloid for the negative which made everything easier. Along with emulsion plates, printing paper was being developed in which the image was no longer formed through exposure to light, but via development in chemicals, after brief exposure. This paper made it possible to make many copies and enlargements, since printing was no longer directly from the subject.

Typographer

Also called printer, is the person who actually performs the printing. In the case of art printing the typographer uses the press or the matrix etched or lithographed. The terms impressit (imp) or stampò or si stampa were used.

Typographer

Also called printer, is the person who actually performs the printing.

Typographical mark

Mark with which the printer and then the publisher or financial backer marks the books printed by himself or on his behalf. The most ancient form is that of the typographical seal placed at the end of the volume together with the colophon, followed by that of the heraldic sign which was placed on the frontespiece. When the publisher and the printer were no longer the same person, it was possible to find the publisher's mark on the title page and the printer's on the colophon.

Watermark

A design, figure or word that is printed on a sheet of paper from copper or bronze wires sewn on the woof of the grid or rods in the middle of the upper half of the framework; the dried pulp thus remained thinner where the wire was located thereby bringing out the drawing. This technique, designed by the papermakers of Fabriano, was to provide a factory label for identification of the origin of the paper, to date manuscripts, and identify the format of books.

Wires

Brass wires stretched on the frame at regular intervals, parallel to the shorter side, on which other wires were woven. These were thinner and more numerous. Called rods, they helped form the base on which the cellulose pulp deposited to make up the sheet of paper. They remained imprinted on the sheet, thereby becoming, along with the watermark, the characteristic elements that identified the format of a book.

Xylography

A relief printing technique carried out on a board. The wood surface is carved with a knife and gouge in the areas that correspond to the blank portions of the sheet. The reliefs (the parts not cut) are then inked by means of a roller and pressed onto the sheet of paper in a printing press.

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