Nathaniel Bowditch (March 26, 1773 - March 16 1838) was an early American mathematician, who wrote on ocean navigation. Bowditch is credited as the founder of modern maritime navigation; his book The New American Practical Navigator, first published in 1802, was carried onboard every commissioned U.S. Naval vessel.

Life and Work

Bowditch, the fourth of seven children, was born in Salem, Massachusetts. When he was 10, Nathaniel had to leave school to work in his father's cooperage. At the age of 12, he was indentured for nine years as a bookkeeping apprentice to a ship's chandler, a retail dealer in nautical provisions and supplies.

When he was 14, he began to study algebra. At 16, he taught himself calculus. He taught himself both Latin and French in order to read mathematical works. At the age of 17, he wrote a letter to a Harvard University professor pointing out an error in Isaac Newton's Philosophiae Naturalis Principia Mathematica. When only 18, he copied all the mathematical papers he found in the Transactions of the Royal Society of London.

There was one aspect of serendipity in Bowditch's self-studies. Richard Kirwan (1733-1812) was an Irish chemist who made contributions in several areas of science. Kirwan was elected to the Royal Society of London in 1780 and helped found the Royal Irish Society some years later. A privateer from Salem, that is a sailor licensed to attack enemy shipping, had intercepted a ship carrying Kirwan's library between Ireland and England and having captured it brought Kirwan's library back to Salem where it was available and used by Bowditch from June 1791. Bowditch had begun to learn algebra in 1787 and two years later he began to study the differential and integral calculus. He learned calculus so that he might study Newton's Principia and in 1790 he learned Latin, which was also necessary to enable him to read Newton's famous work. Later Bowditch learned other languages in order to study mathematics in these languages; in particular he learned French in 1792.

In 1795, Bowditch went to sea on the first of four voyages as a ship's clerk and captain's writer. His fifth voyage was as master and part owner of a ship, after which in 1803 he returned to Salem and left seafaring to take up his mathematical studies and enter the insurance business. (One of his family homes in Salem, the Nathaniel Bowditch House, still exists and has recently been restored.) Among the many other significant scientific contributions by Nathaniel Bowditch was a translation of Pierre-Simon Laplace's Méchanique céleste, a lengthy work on mathematics and theoretical astronomy.

In 1804, he became president of the Essex Fire and Marine Insurance Company in Salem and under his leadership the Company prospered despite difficult conditions due to the War of 1812 and other political problems. During the years of his presidency of this company, Bowditch undertook mathematical and astronomical investigations that gave him a high reputation in the academic world.

Bowditch was the first insurance actuary in this country, in which capacity he headed up of the Essex Fire and Marine Insurance Company.

Bowditch received high recognition for his academic contributions, including election to the American Academy of Arts and Sciences in 1799. He was offered the chair of mathematics and physics at Harvard in 1806, but he turned it down. In 1804, he had published an article on observations of the moon, and in 1806 he published naval charts of the harbor at Salem and several other harbors. More scientific publications followed, such as one on a meteor explosion in 1807, three papers on orbits of comets (1815, 1818, 1820) and in 1815 he studied Lissajous figures while studying the motion of a pendulum suspended from two points.

Harvard was not the only one to offer Bowditch a chair. He was also offered one by West Point and, in 1818, he was offered the chair at the University of Virginia. However, Bowditch had a salary from the Essex Fire and Marine Insurance Company that was 50% higher than the $2,000 that Virginia offered him. Bowditch refused all the chairs of mathematics he was offered.

Bowditch's translation of the first four volumes of Laplace's Traité de mécanique céleste was completed by 1818, but he would not publish it for many years. Almost certainly, the cost of publication caused the delay, but Bowditch did not just put the work on one side after 1818. Instead, he continued to improve it over the succeeding years. Bowditch was helped by Benjamin Pierce in this project and his commentaries doubled the length of the book.

By this time, Bowditch had a high international reputation for he had published articles in British and Continental journals as well as in American ones. He was elected to the American Philosophical Society in 1809, the Royal Society of Edinburgh and the Royal Society of London both in 1818 and the Royal Irish Academy in 1819.

In 1823, Bowditch left the Essex Fire and Marine Insurance Company and became an actuary for the Massachusetts Hospital Life Insurance Company. At Mass. Hospital Life, he served as what would today be called a "money manager" for wealthy individuals who made their fortunes at sea. In essence, Bowditch redirected New England wealth from maritime investment to manufacturing investment, helping create the mills that made Lowell, Massachuesetts prosperous.

When Bowditch moved from Salem to Boston in 1823, he moved 2,500 books, more than 100 maps and charts and 29 volumes of his own manuscripts.

The American Practical Navigator

During his time at sea, Bowditch became intensely interested in the mathematics involved in celestial navigation. He worked initially with John Hamilton Moore's London-published "Navigator", which was known to have errors. To have exact tables to work from, Bowditch recomputed all of Moore's tables, and rearranged and expanded the work. He contacted the US publisher of the work, Edmund Blunt, who asked him to correct and revise the third edition on his fifth voyage. The task was so extensive that Bowditch decided to write his own book, and to "put down in the book nothing I can't teach the crew." On that trip, it is said that every man of the crew of 12, including the ship's cook, became competent to take and calculate lunar observations and to plot the correct position of the ship.

In 1802 Mr. Blunt published the first edition of the American Practical Navigator, which became the western hemisphere shipping industry standard for the next century and a half. The text included several solutions to the spherical triangle problem that were new, as well as extensive formulae and tables for navigation. In 1866, the United States Hydrographic Office purchased the copyright and since that time the book has been in continuous publication, with regular revisions to keep it current. Bowditch's influence on the American Practical Navigator was profound that to this day mariners refer to it by simply as Bowditch.

Nathaniel Bowditch died in Boston, Massachusetts in 1838, by Lactosis. He is buried in Mount Auburn Cemetery, where a monument to him was erected through public collections.

The following eulogy was written by the Salem Marine Society:

In his death a public, a national, a human benefactor has departed. Not this community nor our country only, but the whole world has reason to do honor to his memory. When the voice of eulogy shall cease to flow, no monument will be needed to keep alive his memory among men; but as long as ships shall sail, the needle point to the north, and the stars go through their wonted courses in the heavens, the name of Dr. Bowditch will be revered as of one who has helped his fellowmen in time of need, who was and is a guide to them over the pathless oceans, and one who forwarded the great interests of mankind.

A lunar crater is named after Nathaniel Bowditch. Lunar craters are often given the name of a prominent scientist.

In 1955, a book for younger readers, Carry On, Mr. Bowditch, was published. It portrays Bowditch's life from his point of view. Nathaniel Bowditch is also the name of a middle school in Foster City, California, which named after him.

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American mathematicians | 1773 births | 1838 deaths | Nathaniel Bowditch