Gilbert disproved, by experiment, many old mystical beliefs about magnetism - such as the notion that lodestone, a
naturally occurring magnetic ore, could cure headaches, and the idea that a magnet could be deactivated by rubbing it
with garlic - and invented the technique of magnetizing pieces of metal using lodestone.
gave the names ‘north pole’ and ‘south pole’ to the two extremities of a bar magnet.
nothing new was added to scientific knowledge of magnetism for two centuries, until the discovery of
electromagnetism in the 1820s and the subsequent work of Michael Faraday
Gilbert realized that there was a distinction between electricity and magnetism (indeed, he coined the term 'electric' in
it was not until the 1730s that the French physicist Charles Du Fay (1698-1739) discovered that there are two kinds
of electric charge, dubbed ‘positive’ and ‘negative’, which behave in some ways like magnetic poles, with like
charges repelling one another and opposite charges attracting one another
The double name came about because a fifteenth-century ancestor of Galileo, called Galileo Bonaiuti, became such an
important figure in society as an eminent physician and magistrate that the family changed their name to Galilei in his
Galileo's father, was an accomplished professional musician who was keenly interested in mathematics and musical theory.
If Aristotle was right, heavy hailstones would have to be manufactured higher in a cloud than lighter hailstones -
the right distance higher up so that, falling at a greater speed, they reached the ground alongside the lighter
hailstones formed at lower ltitudes. It seemed rather unlikely to Galileo, and he delighted in pointing out to his fellow
students and the teachers at the university that a much simpler explanation is that all the hailstones are made in the
same place inside a cloud, so they all fall together at the same speed, whatever their weight.
court mathematician, Ostilio Ricci, was giving a lecture on mathematics to some students. Rather than go away and
come back later, Galileo sat in on the lecture and became fascinated by the subject - his first encounter with
mathematics proper, rather than mere arithmetic. He joined Ricci's students on an informal basis and began to study
Euclid instead of his medical textbooks
Vincenzio refused, on the seemingly reasonable grounds that there were plenty of jobs for doctors but very few for
mathematicians. Galileo just carried on studying mathematics
timed the swing of the pendulum as the arc the chandelier moved over gradually decreased, using his pulse. This led