Dudley, Sir Robert (1573-1649).

6 parts in 2 volumes, volume 1 second edition, volume 2 first edition, folio (530 x 450mm.), illustration: 2 printed title-pages with engraved vignettes, double-page plate of the author's patent of nobility, 216 engraved plates (31 have volvelles or moveable parts), and 146 engraved charts (of which 88 are double-page), binding: contemporary calf over boards, title to volume 2 soiled and strengthened at edge (slight loss), map 4 in book 2 (Carta terza generale d'America) folded with browning and slight loss at folds, in volume 2 some marginal staining affecting edges of first few maps and American section at back, bindings worn, upper cover of volume 1 detached

Phillips, Atlases 457, 458 and 3428; cf. Shirley, British Library M.DUD-1a-1e

The Arcano del mare ("Mystery of the Sea"), is “one of the greatest atlases of the world and one of the most complex ever produced: it is the first sea-atlas of the whole world; the first with all the charts constructed using Mercator’s new projection, as corrected by Edward Wright; the first to give magnetic declination; the first to give prevailing winds and currents; later to be further expanded by Maury and J.T. Towson in the nineteenth century; the first to expound the advantages of ‘Great Circle Sailing’; and perhaps less importantly the first sea-atlas to be compiled by an Englishman, albeit abroad in Italy" (Lord Wardington, "Sir Robert Dudley", in The Book Collector, 52 (2003), nos 2 and 3).

The maps are by English and other pilots and it is generally accepted that the work was both scientific and accurate for the time. Dudley used the original charts of Henry Hudson, and for the Pacific Coast of America used Cavendish's observations. “Abraham Kendall, the master of Dudley’s flagship in the expedition of 1594-95 to explore the 'Eldorador', left notes and plans embodied by Dudley [and] the work of another of this group of famous navigators is represented in a portolano covering the voyage of John Davis to India in 1601” (Phillips, Atlases).

When the first edition appeared Dudley was seventy-three years old. The work consisted of three volumes in different formats; some of the charts had to be folded down several times to make them fit the size of the volumes. This "shortcoming" (as it is called in the Avvertimento to the second edition) was repaired by enlarging the work to two volumes of uniform atlas size and now in two volumes. The sea charts in the second edition are on the whole identical with those of the first edition; Phillips records only minor differences on a few of the maps and the fact that their book is number added to the cartouche.

The work is divided into six books, or sections: book 1 deals with Longitude; book 2 covers errors in the then existing sea-charts, and includes the portolano for the Mediterranean and 15 general maps; book 3 deals with naval and military discipline, notably the former, and there is a long section on naval tactics, especially remarkable for a plan of the construction of a navy in five grades of vessel; book 4 describes the method of designing and building ships of the “Galerato” and "Galizaba" types and is concerned with naval architecture, giving the lines and dimensions of ships; book 5 is devoted entirely to navigation and methods of measuring the sun’s declination and the relative positions of the stars; book 6 contains the sea atlas.

Sir Robert Dudley, self-styled Duke of Northumberland and Earl of Warwick, was an illegitimate son of the Earl of Leicester, the favourite of Queen Elizabeth, and brother-in-law of the circumnavigator Thomas Cavendish. Through the latter he became a close friend of the sea captains John Davies and Abraham Kendall, both expert mariners. In 1594 and 1595 he sailed to the West Indies, attacking the Spanish and exploring the Guiana coasts. He was a skilled mathematician and navigator himself, and this great work was in part compiled from first-hand experience. On his return to England he took part in Essex’s raid on Cadiz in 1596, after which he was knighted. However matrimonial difficulties lost him favour at court, and drove him into permanent exile. In 1605 he settled in Florence, became a Roman Catholic, and entered the service of Cosimo II, Grand Duke of Tuscany. He started preparing the Arcano del mare and employed Antonio Francesco Lucini to engrave the plates.

The Arcano del mare was a monumental and totally original task, the charts, representations of instruments and diagrams all engraved on huge quantities of copper over many years with an exactitude incorporating the minutest detail and printed on the best possible paper. The whole surpassed anything published before and was not equalled in quality until fifty years later in France under Louis XIV.

Antonio Francesco Lucini, the engraver, was born in Florence c. 1610 (or 1605, according to Bénézit). He was a pupil of Callot and a friend of Stefano della Bella. Before being employed by Sir Robert Dudley, he had already published engraved views of Florence and scenes of the Turkish Wars. Lucini put the stamp of his personality on the finished work as well as did the author; the delicacy and strength of the engraving, the embellishments of the lettering “alla cancellaresca”, make it a true example of Italian Baroque art. In a printed introductory leaf found in one copy in the British Library, Lucini states that he worked on the plates in seclusion for twelve years in an obscure Tuscan village, using up to no less that 5,000 lbs of copper. According to the engraver, the Arcano del mare took forty years to prepare and twelve to execute.

The volumes collate as follows:

Volume I.
Book 1. [4], [2], 30pp., illustration: printed title with plate of a navigational instrument pasted on, engraved facsimile of the Patent, 30 engravings on 27 sheets, 22 of which have moveable volvelles, 2 plates cut to neatline and laid down
Book 2. 24pp., illustration: 15 engravings on 9 sheets, 5 of which have volvelles and 15 large (6 double-page or folding) engraved charts, 4 relating to America, 5 of the European coasts, 4 of Asia, and 2 of Africa, 1 plate cut to neatline and laid down, folding maps with some discoloration
Book 3. 25, [1]pp., illustration: 8 engraved plates on 6 sheets (3 plates being of ships in battle formation etc.) and 4 sheets with plates of fortifications and cities with walled defences
Book 4. 12pp., illustration: 18 engravings on 14 sheets (of which 7 are double-page and one has a volvelle) all designs of ships in plan and in section, 2 sheets with engravings cut to neatlines and laid down
Book 5. 26, [2]pp., illustration: 145 engravings on  89 sheets, 38 and have moveable volvelles, 15 sheets with plates cut to neatline and laid down, some volvelles becoming detached

Volume II
Book 6. [2 (printed title with vignette of the great bear)], 60, [2 ("Discorso delle Scienze  Mathematiche”  dated 1648)] pp., illustration: 131 engraved charts (82 double-page), 58 covering Europe, Greenland and Canada , 17 of Africa, 23 of Asia and 33 of America