Bowditch on Solving Lunar Distances

Lunar distance was a complex but important means of determining longitude at sea. It remained useful throughout most of the 19th century as many ship captains could not afford expensive chronometers. Using lunars, longitude could be found with nothing but tables and a octant or sextant. Bowditch was important in navigational history in part because he came up with easier methods for solving lunar distance sight reductions.

This passage is from Bowditch's New American Practical Navigator, 1868, p. 231.

The Mariners Mirrour, 1588

The Mariners Mirrour was the English translation by Anthony Ashley of the Dutch Spieghel der Zeevaerdt by Lucas Janszoon Wagenaer. Published in 1588, it provided, within a single book, a treatise on navigation, sailing directions, and the latest charts for most of Europe. It was so important, and its Dutch creator so well recognized that these types of navigational publications became known in England as "Waggoners."

The title page shows the instruments of a navigator of 1588:

The Method of Using a Cross Staff

The cross staff measures the angle of altitude of the sun or moon or a star by sighting from one end of a staff, past ends of a cross piece, towards the horizon and the celestial object. The cross arm is moved up or down a graduated staff so that when sighting along the staff the user sees the sun or star and horizon at the ends of the cross arm. The altitude is then read off the staff. The altitude is measured on a scale along the staff.

This illustration comes from Medina's Arte De Navegar, 1545.

The English Pilot, Fourth Book

Title page of The English Pilot, Fourth Book, an English sea atlas published from 1671 to 1803, initially by John Seller who was appointed Royal Hydrographer in 1671. These were intended as working charts. The Fourth Book, first issued in 1689 covered North America and Canada.

This edition was published in 1767 and has the water stains that show it went to sea.

It was the first detailed set of sailing directions for the North American coast.

The other books gave charts and sailing directions for England, Europe, and the East Indies.

Certaine Errors in Navigation

Edward Wright broke new ground in navigation with the publication of his book, Certaine Errors in Navigation, Detected and Corrected. It was particularly strong in its mathematical treatment of navigation, the application of Mercator's projection to chart making, and the necessity of noting compass variations when taking bearings. This is the 1610 edition.

University of Virginia Map Library Collection has additional information on Wright's work. 

Time Book at Dix Island Granite Quarry

Time list for granite cut on Dix Island for the Iowa State Capitol outside steps. Dix Island is off Spruce Head, St. George, in southwest Penobscot Bay.

Fish Catch, Schooner Pioneer

Capt. J.W. Lunt of the schooner Pioneer of Tremont kept a log while fishing during the year 1861. The log was used to support a bounty claim from the federal government. This part of the log shows what each fisherman caught each day in September and provided the basis for their federal subsidy. These logs have helped to reconstruct the historic cod catch before good statistics. At this time the schooner was probably hand-lining with the fishermen lining the rail, each with a pair of baited lines.

Letter from General Knox

Signature of Gen'l Henry Knox at end of letter to Robert Houston, surveyor, of Belfast (now Searsport.)

Newspaper Ocean Chronicle

This newspaper Ocean Chronicle, like its predecessor, Pill Garlic, was written and published at sea over a course of years by Captain Edward Payson Nichols, aboard ship. This issue was published aboard the ship Frank Pendleton in 1891. This was purportedly the only newspaper published at sea on a sailing vessel.

Watson Account Book

Shubael Watson created this account book for his store in Arundel, Maine in the 1740s, then brought it with him to Naskeag, now Brooklin, in 1763, shortly after the French left that part of Maine after the loss of the French and Indian War.

The account book shows the sorts of items bought and sold in that period. Molasses, rum, pork, meal (flour), and nails were some items listed for a John Staples in his account for 12 March 1770. This also includes expenses for a trip to Salem.


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