A modern ship navigates with the aid of satellites. The Global Positioning System gives a very accurate location, and computers can calculate the best heading. In the 17th century, however, things were very different. A sailor had to use a compass, cross-staff, chart, pencil and paper and his skills to calculate his latitude and longitude.
There are over 100 navigational instruments in the Museum Boerhaave collection. Most came from the Leiden Observatory and the State Office for the Verification of Marine Instruments (Verificatie van ‘s Rijks Zeeinstrumenten) and date from the 18th and 19th century.
Navigation Instruments
Objecten
Zaksextant
BOX SEXTANT Circular polished brass plates with a lid that, when screwed on the back of the instrument, serves as a handle. Index arm moved by a milled ...
daviskwadrant
BACKSTAFF An ebony frame with pear wood arcs, with brass rivets, one sight vane is original to this instrument. Decorative Suns are found (stamped) on the frame; the ...
Horologium autobarum (klok zee-uurwerk)
HOROLOGIUM AUTOBARUM The physician, mathematician and musician Lotharius Zumbag de Koesfelt (1661-1727) invented this sea clock in 1714. Just as Huygens before he wanted to make a clock ...
Sextant
SEXTANT Ebony frame and limb with a brass index arm and fittings, a wooden handle, and an inlaid ivory plate on the crossbar. The tangent screw is on ...
Zeekijker
NAUTICAL TELESCOPE Nautical telescope, made by the Munich ‘Optical-mechanical Institute’ of Joseph von Utzschneider, which was lead after 1826 by Georg Merz, who bought the company in 1839, ...
Passer
PAIR OF DIVIDERS A pair of cast brass dividers, the steel or iron points have rusted away on the sea bottom and have been replaced by plaster-of-Paris casts. ...
Octant
OCTANT Mahogany frame and limb with a brass index arm and fittings; the back of the limb is also brass-covered, and there is a wooden pad-shaped handle on ...
Sextant in kist
SEXTANT Polished brass frame, a wooden handle with a threaded hole for placing the instrument on a stand. The tangent screw and clamping screw are on the back ...
Zeekijker
'DAY OR NIGHT' TELESCOPE WITH BOX. A manual attached to the inside of the mahogany storage box (40 x 8 x 6) explains that this instrument was called ...
Reflectiecirkel
REFLECTING CIRCLE Circular brown-and-yellow-lacquered brass frame and limb, two wooden handles. The tangent screw, working against a spring load, is on top of the index arm, the clamping ...
Scheepschronometer
MARINE CHRONOMETER IN CANISTER. The director of the Leiden Observatory, Cornelis Ekama bought this chronometer in 1817 together with a regulator. The chronometer is probably of English origin. ...
Jacobsstaf
CROSS-STAFF An ebony staff and four vanes of pear wood. The sky-end of the staff is pyramid-shaped. Vane one is fitted with a brass aperture disk, vane four ...
Chronometer in kist
MARINE CHRONOMETER IN BOX Probably this chronometer was used on ships, while it is mounted in gimbals. Achieved in 1984 by Museum Boerhaave its history is not known. ...
Reflectiecirkel in kist
REFLECTING CIRCLE (Troughton type) Circular polished brass frame, with a wooden handle. A detached U-shaped bracket holds a second handle with a brass-lined threaded hole for a third, ...
Kompas
LIQUID COMPASS Description Circular brass bowl with a glass cover, suspended in gimbals. The bowl is painted white on the inside with a black lubber line, red on ...
Deze pagina
Advanced search
Advanced search
This web exhibit represents only a small selection. Please search for the whole navigational collection in our DATABASE
Compasses
Compasses
The Chinese were the first to discover the properties of the mineral magnetite. The use of this iron ore in compasses began in Europein the late middle ages. With the introduction of steam and the change from wooden to steel in shipbuilding at the end of the 19th century, the compass had to be further developed to function properly in these new conditions.
Latitude
Latitude
In order to navigate, a sailor needs to know his position. The latitude (distance North or South of the equator) can be calculated from the height of the sun during the day or the pole star at night. The first instrument developed for this was the cross-staff, followed by the backstaff. The invention of the octant and its evolution into the sextant and quintant allowed latitude to be found much more accurately.
Longitude
Longitude
The distance East or West was much more difficult to determine than latitude. Longitude errors caused many shipwrecks, but could also lead to new discoveries. Many seafaring countries awarded prizes for potential solutions to the longitude problem. Some men, like Galileo, came up with astronomical proposals. Others tried to develop sea-going clocks, finally resulting in the invention of the chronometer.
Globes and Charts
Globes and Charts
Globes offer the best representation of the earth and were sometimes used on board ship for navigation. For precision, however, one would need an impractically large globe. Instead sailors worked with charts. The first charting aids were written accounts with small sketches of the coastline. These allowed a sailor to orientate himself visually, perhaps with the aid of a telescope. With the invention of the printing press, charts became more accurate and readily available.