Ancient Navigation European Compass and Sundail

Sundial and Compass, France

This combination sundial and compass, most likely a product of seventeenth-century France, functions through two prominent scientific technologies: one that measures time and another that measures location. These two measurements used in combination can provide a complete understanding of a person’s physical and temporal place in the world. Grasping these concepts was of great interest to Europeans at the time of this instrument’s manufacture.

Throughout the fifteenth to early seventeenth centuries, an era deemed the "Age of Exploration," European nations developed a fervent interest in travel as a means to expand trade routes and develop new trade partnerships. It is during this time period that Europeans discovered the Americas and established large-scale colonial networks. The heavy reliance on scientific instruments for ship navigation during this period increased interest in compass and sundial technologies.

History of Sundial Technology 

Sundials are often considered the first scientific instruments, dating back to inception as early as 3500BCE in Egypt. Sundials utilize the measurement of the positions of shadows produced by the sun to determine time of day. Ancient Egyptians initially used shadow clocks or obelisks, which are monumental vertical columns that cast shadows of various lengths and positions depending on the location of the sun. Over time, this primitive sundial technology expanded into other cultures, including the Chinese, Greeks, and Romans, where it was further refined. In addition to the use of an object (technically a "gnomon") that produces a shadow, more advanced sundials rely on a flat dial plane on which times of the day are marked, similar to the face of a clock.

Sundials remained the dominant time-keeping tools until well into the eighteenth century when more convenient clock and wristwatch technology was first developed. These new mechanisms, unlike sundials, could be used indoors and at night without the presence of natural sunlight. During the decades of their initial development, however, clocks depended on sundials against which they could set and measure "true" time.


History of Compass Technology 

Compass technology is used to indicate physical direction. It dates back to the Qin Dynasty in China from 221 to 206BCE when the Chinese first discovered the magnetic properties of lodestones (naturally occurring pieces of iron oxide which attract iron). When a piece of lodestone is freely moving, it reacts with the Earth’s natural magnetism. The Chinese developed this concept further into the magnetic compass by the twelfth century CE, which was soon after brought to Europe likely via the Silk Road trade network. In this more advanced form of technology, a needle is magnetized by a lodestone and positioned upon a pivot around which directional bearings (north, south, east, and west) are marked. The needle reacts with the Earth’s magnetic field and aligns itself pointing toward magnetic north, thus providing a fixed reference point for the compass’s user.

Further technological developments have been made in terms of compass accuracy since the tool's initial development. For example, scholars noticed that the "north" to which a compass needle points is not precisely the same as the geographic North Pole, and it is also not a static point. Scientists now understand that the Earth’s polarity does not run parallel with longitude lines and shifts gradually over time. One must calculate the magnetic declination angle (the angle of error between magnetic north and true geographic north) in order to determine an exact location. Because of this complication involved in compass use, large modern-day ships and airplanes use gyrocompass technology, a function of measurement developed in 1852 that works in conjunction with the Earth’s rotation rather than its magnetism. Additionally, GPS (Global Positioning System) technology, developed and refined in the 1990s, is increasingly utilized in navigation today. This technology uses analysis of satellite signals and time delays to pinpoint an exact position on Earth. Compass technology has not become obsolete for contemporary use.  It can be used in conjunction with a GPS reading to provide direction at a given location. Because a compass is powered by an automatic response to Earth’s magnetism, it also serves as a general standby when wind, state of visibility, or lack of an energy source inhibits the use of more dependent technologies.


The 'Weldon' Pocket Compass and Sundial

The compass-sundial has a lid and a hinged gnomon/style to make it portable. The sundial plate displays roman numerals and is cut away to a 5mm outer edge, allowing the compass rose to be viewed through a glass cover. The compass rose is divided into the basic 16 wind rhumbs with a separate dial showing 360°. North is marked by a fleur-de-lys .The centre of the rose shows a 32-point star. A blue metallic double needle points to both north and south with gold letters denoting both directions.

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The south-pointing chariot

The south-pointing chariot (or carriage) was an ancient Chinese two-wheeled vehicle that carried a movable pointer to indicate the south, no matter how the chariot turned. Usually, the pointer took the form of a doll or figure with an outstretched arm. The chariot was supposedly used as a compass for navigation, and may also have had other purposes.

There are legends of earlier south-pointing chariots, but the first reliably documented one was created by Ma Jun (c. 200–265 CE) of Cao Wei during the Three Kingdoms, about eight hundred years before the first navigational use of a magnetic compass. No ancient chariots still exist, but many extant ancient Chinese texts mention them, saying they were used intermittently until about 1300 CE. Some include information about their inner components and workings.

Legend has it that Huangdi, credited as being the founder of the Chinese nation, lived in a magnificent palace in the Kunlun Mountains.

There was also at this time another tribal leader, Chi You, who was skilled at making weapons and waging war. He attacked the tribe of Yandi, driving them into the lands of Huangdi. Huangdi was angered by this and went to war with Yandi, initially suffering several defeats. At some stage in the fighting Chi You conjured up a thick fog to confound Huangdi's men. They used the south-pointing chariot to find their way and they were ultimately victorious.

Image of South-pointing chariot from Sancai Tuhui (first published 1609).

There were probably several types of south-pointing chariot which worked differently. In most or all of them, the rotating road wheels mechanically operated a geared mechanism to keep the pointer aimed correctly. The mechanism had no magnets and did not automatically detect which direction was south. The pointer was aimed southward by hand at the start of a journey. Subsequently, whenever the chariot turned, the mechanism rotated the pointer relative to the body of the chariot to counteract the turn and keep the pointer aiming in a constant direction, to the south. Thus the mechanism did a kind of directional dead reckoning, which is inherently prone to cumulative errors and uncertainties. Some chariots' mechanisms may have had differential gears. If so, it was probably the first use of differentials anywhere in the world.

History of Chinese Invention - Invention of the Magnetic Compass

As found in the Encyclopedia Britannica, 1999 "Sometime in the 12th century, mariners in China and Europe made the discovery, apparently independently, that a piece of lodestone, a naturally occurring magnetic ore, when floated on a stick in water, tends to align itself so as to point in the direction of the polestar. This discovery was presumably quickly followed by a second, that an iron or steel needle touched by a lodestone for long enough also tends to align itself in a north-south direction." and further that the "Chinese were using the magnetic compass around AD 1100, western Europeans by 1187, Arabs by 1220, and Scandinavians by 1300." This apparently is not a thorough investigation into the origins of the compass, but rather a single observation perhaps from the English scholar Alexander Neckam, who wrote of sailors using a magnetic compass to assist navigation in 1190, De Utensilibus (On Instruments).

Some speculate that in 101 BCE Chinese ships reached the east coast of India for the first time with help from the navigational compass pioneered by the Chinese. They had discovered the orientating effect of magnetite, or lodestone as early as the 4th century BCE. 


The figure to the right shows a working model of the first instrument known to be a compass. The spoon or ladle is of

magnetic lodestone, and the plate is of bronze (non conducting metal). The circular center represents Heaven, and the square plate represents Earth. The handle of the spoon representing the Great Bear, points south.The plate bears Chinese characters which denote the eight main directions of north, northeast, east, southeast, south, southwest, west, northwest, and symbols from the I Ching oracle books which were correlated with directions. Separately marked are the finer gradations of twenty-four compass points, and along the outermost edge are the twenty-eight lunar character representations. Rather than navigation, these simple direction pointers were likely used for geomancy or Fung Shui, the technique of aligning buildings according to forces of nature.    

    

Float Comass

The bowl of water with edge markings (to the left) shows a simple mariner's compass, with a floating magnetized needle pointing north and south.By the time of the T'ang dynasty (7-8th century CE) , Chinese scholars had devised a way to magnetize iron needles, by rubbing them with magnetite, and then suspending them in water (early 11th century). They also had observed that needles cooled from red heat and held in the north-south orientation (the earth's axis) would become magnetic. These more refined needle compasses could then be floated in water (wet compass), placed upon a pointed shaft (dry compass) or suspended from a silk thread. Consequently, they were much more useful for navigation purposes since they were now much more portable (and smaller).

A further refinement in the box compass (to the right) is from about 1200 CE, and is much more suitable for navigation. It retains markings of the heaven's plate around its circumference, in a simplified form. Compass markings generally had an inner circle with the eight trigrams and an outer circle with 24 directions based on azimuth points. 

Box Compass

Reposted From Computer Smiths

Ship Positioning in Navigation in the Olden Days:

Dead Reckoning

This ancient form of navigation known as dead reckoning begins with a known position, or fix, which is then advanced, mathematically or directly on the chart, by means of recorded heading, speed, and time.

The navigator finds a position by measuring the course and distance they have sailed from some known point. Starting from a port, the navigator measures the distance from that point on a chart. Each day’s end position would be the starting point for the next day’s course and distance-measurement.

 
The navigator plots his 9am position, indicated by the triangle, and, using his course and speed, estimates his position at 9:30am and 10am.

Without an accurate way to tell time, dead reckoning was notoriously inaccurate in the open ocean, making Columbus’s feats all the more remarkable.

Compass

 

A compass is a navigational instrument that shows directions in a frame of reference that is stationary relative to the surface of the Earth. The frame of reference defines the four cardinal directions (or points) – north, south, east, and west. Intermediate directions are also defined. Usually, a diagram called a compass rose, which shows the directions (with their names usually abbreviated to initials), is marked on the compass.

One of their first contributions of China was the invention of the magnetic compass. The first definitive reports that the Chinese were aware of magnetism date to 240 B.C.

Chinese scientists knew as early as the third century AD that iron ore, called magnetite, aligned itself in North/South position. They learned that by heating pieces of ore and then placing the pieces in a North/South position, they could make a magnet. The magnet was then placed on a piece of reed and floated in bowl of water marked with directional bearings.

Admiral Zheng He is China's most famous maritime explorer. His extraordinary ability and vision found brilliant expression in the great achievements of his life, including maritime exploration, foreign diplomacy, and military affairs.

Records show that Zheng He of Yunnan (1371-1435) used the device during his voyages. Based on the history of the compass, these voyages took place between 1405 to 1433.

To navigate throughout the Indian Ocean, Zheng He would have made use of the magnetic compass, invented in China during the Song dynasty. Photo credit: © WGBH Educational Foundation

Marine Chronometer 

 A marine chronometer designed by at sea by Yorkshire-born John Harrison was critical to success of Captain Cook.

Until the 28th century, there were no clocks that could accurately keep time at sea – the rolling waves, changes in temperature and humidity played havoc with the delicate, inner workings of any mechanical timepiece. The quest for an accurate way to calculate longitude reached fever pitch by the end of the 1700s. In England, Parliament offered a prize to anyone who could solve the riddle.

Using a combination of different metals, ingenious design and painstaking trial and error, Harrison took four years to build his first spring-driven friction-free device.

 Drawings of Harrison's H4 chronometer of 1761, published in The principles of Mr Harrison's time-keeper, 1767