Magnetism has been known and studied for centuries, with early uses including compasses by ancient Greeks, Romans, and Chinese. In the 13th century, Petrus Peregrinus mapped the magnetic field of a lodestone and discovered magnets have north and south poles. William Gilbert established in 1600 that Earth acts as a giant magnet. Later, scientists like John Michell, Charles Coulomb, Hans Christian Oersted, Andre-Marie Ampere, Dominique Arago, Michael Faraday, and Joseph Henry explored connections between electricity and magnetism, with Faraday inventing the dynamo and electric motor. James Clerk Maxwell then published a complete theory of electromagnetism in the 19th century.

1. Timeline of Magnetism
Group 3

2. Ancient World:
Magnetism is know to the ancient
Greeks, Romans, and Chinese.
The Chinese used geomantic
compasses in Feng Shui.
Magnets gained their name from
Manisa in Turkey, a place once
named Magnesia, where magnetic
lodestone was found in the ground

3. Geomantic compass

4. 13th century: Petrus Perigrinus
Magnetic compasses were first used for
navigation in western nations. Frenchman
Petrus Perigrinus, also called Pierre de
Maricourt, mapped the magnetic field of a
lodestone with a compass and discovered
that a magnet had two magnetic poles:
north and south poles.

5. Compass

6. 17TH Century: William Gilbert
English physician and scientist William
Gilbert (1544-1603), physician of
Queen Elizabeth I, published De
Magnete (On Magnets) in 1600, his
monumental scientific study of
magnetism, and proposed that Earth is
a giant magnet.

7. 18th Century: John Michell and
Charles Augustin de Coulomb
Englishman John Michell (1724-93) and
Frenchman Charles Augustin de Coulomb
(1736-1806) studied the forces magnets
can exert. Coulomb also made important
studies of electricity, but failed to connect
electricity and magnetism as parts of the
same underlying phenomenon.

8. Torsion Balance

9. John Michell
Charles Augustin de
Coulomb

10. 19th Century
Danishman Hans Christian Oersted
(1777-1851), Frenchmen André-
Marie Ampère (1775-1836) and
Dominique Arago (1786-1853), and
Englishman Michael Faraday (1791-
1867) explored the close
connections between electricity and
magnetism.

11. Andre-Marie Ampere Dominique Arago

12. Hans Christian Oersted
Oersted arrived to this
conclusion after discovering that
an electric current flowing
through a wire can cause a
compass needle to deflect.

13. visualize

14. Joseph Henry and Micheal Faraday
Faraday and American Joseph Henry (1797-1878)
independently discovered that a changing magnetic
field produced a current in a coil of wire Faraday,
who was perhaps the greatest experimentalist of all
time, came up with the idea of electric and magnetic
"fields" and invented the dynamo (a generator),
along with one of the first electric motors.

15. Micheal Faraday Joseph Henry

16. EXAMPLE:

17. James Clerk Maxwell
James Clerk Maxwell (1831- 1879)
published a relatively complete
explanation of electricity and
magnetism (called the theory of
electromagnetism) and suggested
that electromagnetic energy travels
in waves

18. visualize

19. Pierre Curie
Pierre Curie (1859-1906)
demonstrated that materials lose
their magnetism above a certain
temperature now known as Curie
point

20. visualize

21. Wilhelm Weber
Wilhelm Weber (1804- 1891)
developed practical methods for
detecting and measuring the
strength of a magnetic field.