A Chart of Magnetic Curves of Equal Variation.
1844 (undated) 10.5 x 16 in (26.67 x 40.64 cm)
1 : 86000000
This is a fine example of Adam and Charles Black's 1844 chart of the World's Magnetic Curves of equal variation. The chart depicts the magnetic curves over the entire world, but does not show the isomagnetic lines over any continent except North America. It marks the northern magnetic pole at the Boothia Felix (now the Boothia Peninsula) based on the first expedition by James Clark Ross in 1831. Due to the magnetic changes in the Earth's core, the position of the magnetic pole changes over time. In 2005, it was estimated that the northern magnetic pole was positioned to the west of Ellesmere Island in Canada. Throughout, the map identifies various cities, rivers and an assortment of additional topographical details. It names various countries, but no boundaries are depicted. The map is engraved by G. Aikman and issued as plate no. III-I in the 1844 edition of Black's General Atlas.
Charles and Adam Black (fl. 1807 - present) were map and book publishers based in Edinburgh. Charles and his uncle, Adam, both of Edinburgh, Scotland, founded their publishing firm in 1807. They published a series of maps and atlases throughout the 19th century. In addition to an array of atlases, the Black firm is known for their editions of the Encyclopedia Britannica (1817 - 1826) and the first publishing of Sir Walter Scott's novels in 1854. In 1889 the A. & C. Black publishing house moved to London where it remains in operation to this day.
George Aikman (December 28, 1788 - October 16, 1865) was a Scottish printer, lithographer, and engraver active in the early 19th century. Aikman most likely apprenticed with his father of the same name, also an engraver, before joining the Edinburgh map and atlas firm of William Lizars. Several years later Aikman established himself independently as "George Aikman and Sons, Engravers and Lithographers", publishing numerous maps and prints in conjunction with the larger firm of William and Charles Black, and others. George Aikman's son, also George (1830 - 1905), became an apprentice with the firm around 1842, and eventually a journeyman engraver in Manchester and London, before returning to Edinburgh to take up a full partnership in the family business. Upon the elder Aikman's death in 1865, George became the sole proprietor of the firm and continued to publish until 1876 when he sold the business to pursue a passion for landscape painting.
Black, A. and C., Black's General Atlas (Edinburgh), 1844.
Black's General Atlas was a popular Scottish atlas of the world issued by the Edinburgh firm of Adam and Charles Black. This atlas was first issued in 1840 with subsequent editions being printed well into the 1890s. While most editions were printed in Edinburgh, an American edition was issued in 1857. Most early editions of his atlas were engraved by S. Hall. Typically this refers to Sidney Hall, who died in 1831, but in this case, since the engraving was initiated well after his death, it was most likely his widow, Selina Hall, who did the engraving. Later editions feature additional maps updated and engraved by William Hughes. Early editions featured outline color only, but later editions embraced a full color approach with pale green, yellow, and blue pastels. All editions are known for their meticulous presentation of the most up-to-date cartographic information. Moreover, this exceptionally long publication run provides a fine cartographic record of the middle to late 19th century - particularly as regards the complex cartographic evolution of the Americas through this period.
Very good. Original platemark visible. Blank on verso. Recto an verso repair at two places in left margin.
Rumsey 2305.006 (1854 edition). Philips (atlases) 4334.