If asked to list the inventions that have had the most impact on the world, people would probably come up with the wheel, the clock, the toilet, the printing press, the automobile, electricity, the telephone, TV, antibiotics, vaccines, the computer and the Internet... and maybe chocolate bars.
But what about the compass? This modest device, a floating magnetized needle, has been given little credit. But now an Israeli who grew up on a ship's deck and was taught to navigate the Mediterranean before he learned to drive has written a book in Hebrew dedicated to "the invention that changed the face of the world."
Called Hidat Hamatzpen (The Riddle of the Compass), Amir Aczel's book was originally published in English in New York; it has now been printed in Israel and released by Aryeh Nir Publishers of Tel Aviv. The NIS 76, 158-page softcover volume, whose hardcover English version was highly praised in The New York Times, The Washington Post and other papers, is the result of Aczel's historical-scientific investigation. Based on dozens of ancient, medieval and modern sources, the book explains how different the world would be if this simple seafarer's tool had not been invented. Many of these sources were not in English, and include manuscripts written in China and Europe centuries ago.
THE SEAS and oceans were the highways of commerce from ancient times, notes Aczel, who now lives with his wife and daughter near Boston, lectures in mathematics at Bentley College, and is the author of several other books, including Fermat's Last Theorem, God's Equation, The Mystery of the Aleph and Probability 1. But these waterways were unusable for many months of the year; when the skies were overcast, depending on the winds, sun and stars to find one's way was impossible. At night, mariners sought out Polaris (the North Star) by looking for a familiar nearby constellation. But the early seafarers had difficulty finding their way and knowing when they were nearing land even when the skies were clear. Many never sailed out of the sight of the shore, although this was dangerous; ships often ran aground.
The biblical Noah was the first person in recorded history to use birds to determine how far he was from land - after the Flood began to recede near Ararat, he dispatched a dove, which returned to his ark with an olive branch in its beak. Aczel notes that the Vikings were known to take ravens with them on their voyages; when they thought they were nearing land, they released one. If the bird took off, the captain would follow it, hoping to find land, but if the bird returned, it was a sign that the ship was still in open seas.
How do birds and other animals such as fish and bees know how to navigate? The author cites New Zealand researchers headed by Michael Walker, who in 1997 identified a nerve fiber on the front of a fish that releases signals in response to magnetic fields. These University of Auckland scientists also investigated the magnetic senses of the honeybee, the yellow tuna, the red salmon, homing pigeons and a certain whale species.
"It is very likely that many species of birds, reptiles and mammals are able to find their direction in relation to the magnetic poles of our world," he writes.
It may be that Walker and his colleagues identified the mechanism that enables creatures to find their way far from any familiar landscape. With such innate compasses, these animals were used by ancient mariners before the invention of the mechanical compass.
The earth, which has a liquid iron core, is a giant magnet that generates a magnetic field. The author notes that the North Pole was not always in the north and the South Pole in the south. A few hundred thousand years ago, the poles switched to their present location, according to scientists who have found rocks made up of elements whose atoms were aligned differently before becoming fixed in solids.
No one knows what caused the switch, says Eczel, or when the next one will occur.
"If you had taken to sea in a boat 300,000 years ago, before the last polar switch, the needle of your compass would have pointed south and not north."
ACZEL SAYS he first developed an interest in compasses as a child. His Israeli father was a ship's captain, and he spent much of his youth - except for a few months a year at school - at sea. When he was 10, he was entrusted with the ship's wheel while standing on a stool and rotating it to the compass points given him by his father. During one of their voyages to the town of Amalfi in Italy, they visited the Compass Hotel. This establishment was named for the alleged inventor of the modern magnetic compass, Flavio Gioia, who lived there in late 13th and early 14th century, when it was an Italian city-state. Some maintain that Gioia never existed, but there is a statue in his memory.
But while Amalfi claims to be the birthplace of the compass's inventor, Aczel and other scholars give the real credit to China.
"The compass," he writes, "was invented in antiquity in China, where it did not immediately improve navigation but was used in feng shui" - the Chinese art of finding the "right" location and environment for objects. According to this belief, says Aczel, the winds are the spirit that flow through the Earth's arteries, and water cleanses and renews the face of the land and its residents.
"Feng shui therefore belongs to the field of cosmic spirituality, and it thus provided an important service in traditional Chinese culture."
At the beginning of the Common Era, the Chinese were the first to notice that loadstone - a mineral ore also known as magnetite or ferrite oxide (Fe3O4 always points north when it floats on water. Large deposits of the mineral were found in Asia Minor's district of Magnesia. Chinese fortune tellers are known to have used lodestones to construct their fortune-telling boards.
However, it was indeed the mariners of Amalfi, then a maritime city-state in Italy, who turned the loadstone into the compass we know today. A delay of almost 14 centuries passed between the first recorded instance of a compass being used to show direction and the device being used to aid navigation.
"It seems to be a law of nature that a technology is developed and then waits a long time for people to discover their need for it, rather than the other way around," writes Aczel, who documents how the compass led to the development of navigation, the Age of Exploration, the discovery of new continents and the expansion of European kingdoms. Although many records have been lost, the author maintains that the Chinese kept their invention of the compass and its use on ships secret until the 11th century because these were used to transport "non-believers."
THE ITALIAN explorer Marco Polo, born around 1254 in the great commercial center of Venice, was the first European to travel to China. He was thought to have brought a magnetic compass with him when he returned after two decades of service in the court of Kublai Khan. But Aczel contends that while Marco Polo may have brought back such a souvenir, he was not the one who introduced it to Europe.
By the end of the 13th century, many European ships were equipped with compasses. Captains no longer had to remain at port during cloudy seasons, and were allowed to set off any time of the year. Since they were sailing ships, the winter winds promised faster and more distant travel. The oceans were mapped, thanks to the compass, and many of these same routes are used today.
Aczel notes that some 35 years ago, when he and his father crossed the Atlantic on a ship named the Theodor Herzl, they were overtaken by a hurricane.
"When we neared the eye of the storm, the waves towered. But my father had a wonderful device that helped him avoid the most dangerous parts of the storm. On the wall of his map room was a grey machine. When he pressed a button, it printed out on bluish paper a weather report broadcast to it. It was a map made up of many dots showing the location of the storm and its force."
That device was a primitive fax machine. Used primarily by sailors and pilots, it became a common household device many years later.
"I still remember the sensation that the fax machine created when introduced for the popular market. Would you believe that people could get menus from restaurants by fax?"
Not only the compass and the fax, but numerous other technologies - such as color TV, cellular phones, global positioning systems and the Internet, to mention only a few - were available for decades before someone figured out a popular use for them. But the compass - "the first technological invention to change the world since the wheel" - clearly captured Aczel's heart.