Aristotle

Aristotle (Physics)

Living in the same time period as Plato and Alexander. Aristotle helped lay the foundations for western civilisation through his wide range of intellectual and scientific studies.

Aristotle was one of the great polymaths of his time. He studied under Plato and therefore learnt much about the great philosophic traditions of Socrates. But, Aristotle was more than just a good student; he had an independent mind and was able to question many different things and sought to resolve difficult questions and previously unsolvable problems. He made studies in botany, physics, philosophy, logic, and was well known for being a powerful lecturer and debater. He was also regarded as a kindly man, compassionate to others.

In the field of physics, Aristotle’s ideas influenced much of the medieval period, and lasted into the European Renaissance. His ideas were later replaced by the physics of Isaac Newton.

Aristotle believed in the power of reason to illuminate the problems of man. He believed that man had the capacity for enlightenment through self inquiry and study. He believed that human goodness derived from rational thought. Aristotle was also a playwright and he described how the weakness of man – pride, anger, jealousy, could lead to his downfall.

Aristotle was also the teacher of the future Macedonian King – Alexander the Great. Aristotle taught the future king, political philosophy, history and ethics. Alexander the Great was to ignore much of Aristotle’s teachings such as the desirability of oligarchic leadership, but, his education by Aristotle must have left an abiding impression on the young prince.

Aristotle, was one of the few philosophers who strongly influenced later Christian writers such as Thomas Aquinas.

Otto Hahn

Otto Hahn

Otto Hahn (1879-1968) was a German Chemist, who was awarded the Nobel Prize for Chemistry in 1944 – for his work in discovering Nuclear Fission. He was a distinguished Chemist who worked in the pioneering fields of radio chemistry. After the Second World War, he was a campaigner against the use of nuclear weapons and became an influential scientific figure in West Germany.

Otto Hahn was born in Frankfurt on 8th March, 1879. From an early age, he took an interest in Chemistry, and was supported by his prosperous parents. He studied chemistry at the University of Marburg and earned his doctorate in 1901. After a years military service, he worked as an assistant at the University of Marburg, before travelling to London, England.

He went to the University College, London and worked under Sir William Ramsay. Hahn hope to improve his knowledge of chemistry and English to help his professional career. In early 1906, he visited Montreal, where he spent a brief but fruitful time with Ernest Rutherford, where they investigated alpha-rays of radio actinium.

In 1906, he returned to Germany where he collaborated with Emil Fischer at the University of Berlin. With just a basic chemistry laboratory, Hahn discovered Meothorium, and the mother substance of radium, ionium. This discovery later had a great practical use for radiation treatment.

In 1907, he began a long working relationship with the Jewish Austrian physicist, Lise Meitner. They remained life-long friends though she later criticised him for not doing enough to oppose the Nazi regime and their persecution of Jews. Though Hahn did help a few Jewish scientists, and played a role in helping Meitner herself to escape to Sweden in 1938, after the Anschluss forced her to flee.

In 1910, he was appointed professor at the Kaiser Wilhelm Institute for Chemistry, where he became head of the radiochemistry department.

During the First World War, Hahn was conscripted into the German army and put to work on developing chemical warfare. He participated in developing and organising the use of poison gases, such as Chlorine and Mustard Gas on both the Western and Eastern fronts.

After the war, Hahn concentrated on the chemistry of radioactive elements. In 1921, with Lise Meitner, they made a very important discovery of Uranium Z – the first example of nuclear isomers. Although few paid much attention, this would prove very important in later nuclear physics.In 1936, he produced a book “Applied Radiochemistry” which became a very significant milestone in radiochemistry. 

During his time of internment, he was awarded the 1944 Nobel Prize for Chemistry ‘for his discovery of the fission of heavy atomic nuclei’ He was unable to attend because of his internment in England. Some scientists have argued his colleague Meitner should have been awarded the prize jointly.

Hahn was shocked to learn that the atomic bomb had been dropped on Japan in 1945, to devastating effect. He felt guilty that he, in some way, may have been responsible for this great loss of life.

After the Second World War, he campaigned against the use of Nuclear weapons, and in 1955 initiated the Mainau Declaration which warned of the dangers of atomic weapons. He became a leading figure within post war FDR, and was a high profile critic of rearming West Germany with atomic weapons. His opposition to the nuclear arms race caused him to be nominated for the Nobel Peace prize.

In 1966, he was awarded the Enrico Fermi Prize – the only time it has been awarded to a non-American.

Between 1948 to 1960, Hahn was the founding President of the Max Planck society for the advancement of science. Otto Hahn died in West Germany on 28th July, 1968.

Charles Darwin

Charles Darwin

Charles Darwin was an English Natural scientist who laid down a framework for the theory of evolution – showing how Man evolved from lower life forms. At the time, his research and publication led to bitter controversy, but his theory of evolution and natural selection became accepted within the scientific community.

Charles Darwin was born on 12 February 1809 in Shrewsbury, Shropshire. He was born in to a wealthy and influential family. His grandfathers included – china manufacturer Josiah Wedgwood, and Erasmus Darwin, one of the leading intellectuals of 18th century England.

Darwin planned to study medicine at Edinburgh university, but later, at the instigation of his father, changed to studying Divinity at Christ’s College, Cambridge University. Darwin was not a great student, preferring to spend time in outdoor pursuits, he spent a lot of time examining natural science and beetle collecting. After gaining a passionate interest in natural science, Darwin was offered a place on the HMS Beagle to act as natural scientist on a voyage to the coast of South America.

At the time, religion was a powerful force in society, and most people took the Bible as the infallible, literal word of God. This included the belief that God created the world in seven days, and the world was only a few thousand years old. However, on the voyage, Darwin increasingly began to see evidence of life being much older. In particular Lyell’s ‘Principles of Geology’ suggested that fossils were evidence of animals living hundreds of thousands of years ago.

On the voyage, Darwin made copious notes about specimens he found on his voyages. In particular, at the Galapagos Islands 500 miles west of South American, Darwin was struck by how the Finch was different on each individual island. He noticed that the Finch had somehow adapted to the different aspects of the particular island.

Over the next 20 years, Darwin worked on the dilemma of how species evolve and can end up being quite different on different islands. Influenced by the work of Malthus, Darwin came up with a theory of natural selection and gradual evolution over time.

Darwin continued to refine his theory, and would intensively breed plants to work on his theories. However, realising how controversial his ideas were, Darwin delayed publishing them. It was not until learning that another naturalist, Alfred Russel Wallace, had developed similar ideas, that Darwin was galvanised into publishing his own book.

In 1859, the ground-breaking ‘On the Origin of Species by Means of Natural Selection’ was published. It immediately gained widespread interest and attention, leading to intense debate about the contention that man – by implication was descended from animals like the Ape.

Marie Curie

Marie Curie Biography

Marie Curie was a Polish scientist who won a Nobel prize in both Chemistry and Physics. She was the first female professor of the University of Paris, and made ground-breaking work in the field of Radioactivity.

“Humanity needs practical men, who get the most out of their work, and, without forgetting the general good, safeguard their own interests. But humanity also needs dreamers, for whom the disinterested development of an enterprise is so captivating that it becomes impossible for them to devote their care to their own material profit.”

– Marie Curie

Short Bio Marie Curie

Marya Sklodovska was the youngest of 5 children, born in 1867, Warsaw Poland. She was brought up in a poor but well educated family. Marya excelled in her studies and won many prizes. At an early age she became committed to the ideal of Polish independence from Russia which was currently ruling Poland with an iron fist, and in particular making life difficult for intellectuals. She yearned to be able to teach fellow Polish woman who were mostly condemned to zero education.

Unusually for women at that time, Marya took an interest in Chemistry and Biology. Since opportunities in Poland for further study was limited, Marya went to Paris, where after working as a governess she was able to study at the Sorbonne, Paris. Struggling to learn in French, Marya threw herself into her studies, leading an ascetic life dedicated to studying. She went on to get a degree in Physics finish top in her school. She later got a degree in Maths, finishing second in her school year.

It was in Paris, that she met Pierre Curie, who was then chief of the laboratory at the school of Physics and Chemistry. He was a renowned Chemist, who had conducted many experiments on crystals and electronics. Pierre was smitten with the young Marya and asked her to marry him. The unromantic Marya initially refused, but, after persistence from Pierre she relented. The two would later become inseparable, until Pierre’s untimely death.

Marie Curie work on Radioactivity

Marie pursued studies in radioactivity. In 1898, this led to the discovery of two new elements. One of which she named polonium after her home country.

There then followed 4 years of extensive study into the properties of radium. Using dumped uranium tailings from a nearby mine, they were very slowly, and painstakingly, able to extract a decigram of radium.

Radium was discovered to have remarkable impacts. Marie actually suffered burns from the rays. It was from this discovery of radium and its properties that the science of radiation was able to develop. Using the properties of radium to burn away diseased cells in the body. Initially radiotherapy was called ‘currietherapy’

The Curries agreed to give away their secret freely; they did not wish to patent such a valuable element. The element was soon in high demand and it began industrial scale production.

For their discovery they were awarded the Davy Medal (Britain) and the Nobel Prize for physics in 1903.

In 1905, Pierre was killed in a road accident, leaving Marie to look after the laboratory and her 2 children.

In 1911 she was awarded a second Nobel prize in Chemistry for the discovery of actinium and further studies on radium and polonium.

The success of Marie Curie also brought considerable hostility, criticism and suspicion from a male dominated science world. She suffered from the malicious rumours and accusations that flew around.

The onset of World War I in 1914, led to Marie Curie dedicating her time to the installation of X ray machines in hospitals. Marie understood that x ray machines would easily be able to located shrapnel, enabling better treatment for soldiers. By, the end of the first world war, over a million soldiers had been examined by her X ray units.

Marie Curie died in 1934 from Cancer. It was an unfortunate side effect of her own ground-breaking studies into radiation which were to help so many people.

Isaac Newton

Isaac Newton is perhaps the greatest physicist who has ever lived. He and Albert Einstein are almost equally matched contenders for this title.

Each of these great scientists produced dramatic and startling transformations in the physical laws we believe our universe obeys, changing the way we understand and relate to the world around us.

Early Life and Education

Isaac Newton was born on January 4, 1643 in the tiny village of Woolsthorpe-by-Colsterworth, Lincolnshire, England.

His father, whose name was also Isaac Newton, was a farmer who died before Isaac Junior was born. Although comfortable financially, his father could not read or write.

His mother, Hannah Ayscough, married a churchman when Newton was three years old.

Newton disliked his mother’s new husband and did not join their household, living instead with his mother’s mother, Margery Ayscough.

His resentment of his mother and stepfather’s new life did not subside with time; as a teenager he threatened to burn their house down!

Beginning at age 12, Newton attended The King’s School, Grantham, where he was taught the classics, but no science or mathematics. When he was 17, his mother stopped his schooling so that he could become a farmer. Fortunately for the future of science Newton found he had neither aptitude nor liking for farming; his mother allowed him to return to school, where he finished as top student.

Servant and Undergraduate

In June 1661, aged 18, Newton began studying for a law degree at Cambridge University’s Trinity College, earning money working as a personal servant to wealthier students.

By the time he was a third-year student he was spending a lot of his time studying mathematics and natural philosophy (today we call it physics). He was also very interested in alchemy, which we now categorize as a pseudoscience.

His natural philosophy lecturers based their courses on Aristotle’s incorrect ideas from Ancient Greece. This was despite the fact that 25 years earlier, in 1638, Galileo Galilei had published his physics masterpiece Two New Sciences establishing a new scientific basis for the physics of motion.

Newton began to disregard the material taught at his college, preferring to study the recent (and more scientifically correct) works of Galileo, Boyle, Descartes, and Kepler. He wrote:

“Plato is my friend, Aristotle is my friend, but my greatest friend is truth.”

Isaac Newton

Mathematician and Physicist

Reading the works of these great scientists, Newton grew more ambitious about making discoveries himself. While still working part-time as a servant, he wrote a note to himself. In it he posed questions which had not yet been answered by science. These included questions about gravity, the nature of light, the nature of color and vision, and atoms.

After three years at Cambridge he won a four-year scholarship, allowing him to devote his time fully to academic studies.

A Mind on Fire

In 1665, at the age of 22, a year after beginning his four-year scholarship, he made his first major discovery: this was in mathematics, where he discovered the generalized binomial theorem. In 1665 he was also awarded his B.A. degree.

By now Newton’s mind was ablaze with new ideas. He began making significant progress in three distinct fields – fields in which he would make some of his most profound discoveries:

• calculus, the mathematics of change, which is vital to our understanding of the world around us
• gravity
• optics and the behavior of light

He did much of his work on these topics back home at Woolsthorpe-by-Colsterworth after the Great Plague forced his college in Cambridge to close.

Fellow and Lucasian Professor of Mathematics

At the age of 24, in 1667, he returned to Cambridge, where events moved quickly.

First he was elected as a fellow of Trinity College.

A year later, in 1668, he was awarded an M.A. degree.

A year after that, the Lucasian Professor of Mathematics at Trinity College, Isaac Barrow, resigned and Newton was appointed as his replacement; he was just 26 years old. Barrow, who had recommended that Newton should succeed him, said of Newton’s skills in mathematics:

“Mr Newton, a fellow of our College, and very young, being but the second year master of arts; but of an extraordinary genius and proficiency.”

Isaac Barrow

Mathematician

Isaac Newton’s Scientific Achievements and Discoveries

Achievements in Brief

Isaac Newton, who was largely self-taught in mathematics and physics:

• generalized the binomial theorem
• showed that sunlight is made up of all of the colors of the rainbow. He used one glass prism to split a beam of sunlight into its separate colors, then another prism to recombine the rainbow colors to make a beam of white light again.
• built the world’s first working reflecting telescope.
• discovered/invented calculus, the mathematics of change, without which we could not understand the behavior of objects as tiny as electrons or as large as galaxies.
• wrote the Principia, one of the most important scientific books ever written; in it he used mathematics to explain gravity and motion. (Principia is pronounced with a hard c.)
• discovered the law of universal gravitation, proving that the force holding the moon in orbit around the earth is the same force that causes an apple to fall from a tree.
• formulated his three laws of motion – Newton’s Laws – which lie at the heart of the science of movement.
• showed that Kepler’s laws of planetary motion are special cases of Newton’s universal gravitation.
• proved that all objects moving through space under the influence of gravity must follow a path shaped in the form of one of the conic sections, such as a circle, an ellipse, or a parabola, hence explaining the paths all planets and comets follow.
• showed that the tides are caused by gravitational interactions between the earth, the moon and the sun.
• predicted, correctly, that the earth is not perfectly spherical but is squashed into an oblate spheroid, larger around the equator than around the poles.
• Used mathematics to model the movement of fluids – from which the concept of a Newtonian fluid comes.
• devised Newton’s Method for finding the roots of mathematical functions.

Some Details about Newton’s Greatest Discoveries

Calculus

Newton was the first person to fully develop calculus. Calculus is the mathematics of change. Modern physics and physical chemistry would be impossible without it. Other academic disciplines such as biology and economics also rely heavily on calculus for analysis.

In his development of calculus Newton was influenced by Pierre de Fermat who had shown specific examples in which calculus-like methods could be used.

Universal Gravitation and the Apple

Newton’s famous apple, which he saw falling from a tree in the garden of his family home in Woolsthorpe-by-Colsterworth, is not a myth.

He told people that seeing the apple’s fall made him wonder why it fell in a straight line towards the center of our planet rather than moving upwards or sideways.

Ultimately, he realized and proved that the force behind the apple’s fall also causes the moon to orbit the earth; and comets, the earth and other planets to orbit the sun. The force is felt throughout the universe, so Newton called it Universal Gravitation. In a nutshell, it says that mass attracts mass.

Newton discovered the equation that allows us to calculate the force of gravity between two objects.

Most people don’t like equations much: E = mc² is as much as they can stand, but, for the record, here’s Newton’s equation:

Dividing by distance squared means Newton’s Law is an inverse-square law.

Newton proved mathematically that any object moving in space affected by an inverse-square law will follow a path in the shape of one of the conic sections, the shapes which fascinated Archimedes and other Ancient Greek mathematicians.

For example, planets follow elliptical paths; while comets follow elliptical, or parabolic or hyperbolic paths.

And that’s it!

Newton showed everyone how to calculate the force of gravity between things such as people, planets, stars and apples.

Newton’s Laws of Motion

Newton’s three laws of motion still lie at the heart of mechanics.

First law: Objects remain stationary or move at a constant velocity unless acted upon by an external force. This law was actually first stated by Galileo, whose influence Newton mentions several times in the Principia.

Second law: The force F on an object is equal to its mass m multiplied by its acceleration: F = ma.

Third law: When one object exerts a force on a second object, the second object exerts a force equal in size and opposite in direction on the first object.

With Newton’s calculus, universal gravitation, and laws of motion, you have enough knowledge at your fingertips to plot a course for a spaceship to any planet in our solar system or even another solar system!

And Isaac Newton figured it all out about 300 years before we actually did send a spaceship to the planets.

A Word of Caution
Newton’s laws become increasingly inaccurate when speeds reach substantial fractions of the speed of light, or when the force of gravity is very large. Einstein’s equations are then required to produce reliable results.

Optics and Light

Newton was not just clever with his mind. He was also skilled in experimental methods and working with equipment.

He built the world’s first reflecting telescope. This telescope focuses light from a curved mirror. Reflecting telescopes have several advantages over earlier telescopes including:

• they are cheaper to make
• they are easier to make in large sizes, gathering more light, allowing higher magnification
• they do not suffer from a focusing issue associated with lenses called chromatic aberration.

Newton also used glass prisms to establish that white light is not a simple phenomenon. He proved that it is made up of all of the colors of the rainbow, which he could recombine to form white light again.

Newton published very little work until his later years, because in his early years as a scientist, Robert Hooke had disagreed strongly with a scientific paper Newton had published. Newton took criticism of his work in a very personal way and developed a lifelong loathing for Hooke.

His lack of published work also caused a huge issue when Gottfried Leibniz starting publishing his own version of calculus. Newton was already a master of this branch of mathematics, but had published very little of it. Again Newton’s insecurity got the better of him, and he angrily accused Leibniz of stealing his work. The pros and cons of each man’s case have long been debated by historians. Most mathematicians regard Newton and Leibniz as equally responsible for the development of calculus.

Newton was a very religious man with somewhat unorthodox Protestant Christian views. He spent a great deal of time and wrote a large body of private works concerned with theology and his interpretation of the Bible.

His scientific work had revealed a universe that obeyed logical mathematical laws. He had also discovered that starlight and sunlight are the same, and he speculated that stars could have their own systems of planets orbiting them. He believed such a system could only have been made by God.

Michael Faraday

Michael Faraday, whose family was very poor, became one of the greatest scientists in history. His achievement was remarkable in a time when science was the preserve of people born into privileged families.

Education and Early Life

Michael Faraday was born on September 22, 1791 in London, England. He was the third child of James and Margaret Faraday. His father was a blacksmith who had poor health. Before marriage, his mother had been a servant. The family lived in a degree of poverty.

Michael Faraday attended a local school until he was 13, where he received a basic education. To earn money for the family he started working as a delivery boy for a bookshop. He worked hard and impressed his employer. After a year, he was promoted to become an apprentice bookbinder.

Bookbinding and Discovering Science

Michael Faraday was eager to learn more about the world; he did not restrict himself to binding the shop’s books. After working hard each day, he spent his free time reading the books he had bound.

Gradually, he found he was reading more and more about science. Two books in particular captivated him:

The Encyclopedia Britannica – his source for electrical knowledge and much more; and the 600 page Conversations on Chemistry by Jane Marcet – his source for chemistry knowledge.

He became so fascinated that he started spending part of his meager pay on chemicals and apparatus to confirm the truth of what he was reading.

As he learned more about science, he heard that the well-known scientist John Tatum was going to give a series of public lectures on natural philosophy (physics). To attend the lectures the fee would be one shilling – too much for Michael Faraday. His older brother, a blacksmith, impressed by his brother’s growing devotion to science, gave him the shilling he needed.

Introduction to Humphry Davy and More Science

Faraday’s education took another step upward when William Dance, a customer of the bookshop, asked if he would like tickets to hear Sir Humphry Davy lecturing at the Royal Institution.

Sir Humphry Davy was one of the most famous scientists in the world. Faraday jumped at the chance and attended four lectures about one of the newest problems in chemistry – defining acidity. He watched Davy perform experiments at the lectures.

This was the world he wanted to live in, he told himself. He took so many notes and then made additions to the notes that he produced a 300 page handwritten book, which he bound and sent to Davy as a tribute.

At this time, Faraday had begun more sophisticated experiments at the back of the bookshop, building a electric battery using copper coins and zinc discs separated by moist, salty paper. He used his battery to decompose chemicals such as magnesium sulfate. This was the type of chemistry Humphry Davy had pioneered.

In October 1812, Faraday’s apprenticeship ended, and he began work as a bookbinder with a new employer, whom he found unpleasant.

And then there was a fortunate (for Faraday) accident. Sir Humphry Davy was hurt in an explosion when an experiment went wrong: this temporarily affected his ability to write. Faraday managed to get work for a few days taking notes for Davy, who had been impressed by the book Faraday had sent him. There were some advantages to being a bookbinder after all!

When his short time as Davy’s note-taker ended, Faraday sent a note to Davy, asking if he might be employed as his assistant. Soon after this, one of Davy’s laboratory assistants was fired for misconduct, and Davy sent a message to Faraday asking if he would like the job of chemical assistant.

Would he like the job? Working in the Royal Institution, with one of the most famous scientists in the world? There could only be one answer!

Michael Faraday’s Career at the Royal Institution

Faraday began work at the Royal Institution of Great Britain at the age of 21 on March 1, 1813.

His salary was good, and he was given a room in the Royal Institution’s attic to live in. He was very happy with the way things had turned out.

He was destined to be associated with the Royal Institution for 54 years, ending up as a Professor of Chemistry.

Faraday’s job as a chemical assistant was to prepare apparatus for the experiments and the lectures at the Royal Institution.

At first, this involved working with nitrogen trichloride, the explosive which had already injured Davy. Faraday himself was knocked unconscious briefly by another nitrogen chloride explosion, and then Davy was injured again, finally (thankfully) putting to an end to work with that particular substance.

After just seven months at the Royal Institution, Davy took Faraday as his secretary on a tour of Europe that lasted 18 months.

Michael Faraday’s Scientific Achievements and Discoveries

It would be easy fill a book with details of all of Faraday’s discoveries – in both chemistry and physics. It is not an accident that Albert Einstein used to keep photos of three scientists in his office: Isaac Newton, James Clerk Maxwell and Michael Faraday.

Funnily enough, although in Faraday’s lifetime people had started to use the word physicist, Faraday disliked the word and always described himself as a philosopher.

He was a man devoted to discovery through experimentation, and he was famous for never giving up on ideas which came from his scientific intuition.

If he thought an idea was a good one, he would keep experimenting through multiple failures until he got what he expected; or until he finally decided that mother nature had shown his intuition to be wrong – but in Faraday’s case, this was rare.

Here are some of his most notable discoveries:

1821: Discovery of Electromagnetic Rotation

This is a glimpse of what would eventually develop into the electric motor, based on Hans Christian Oersted’s discovery that a wire carrying electric current has magnetic properties.

1823: Gas Liquefaction and Refrigeration

In 1802, John Dalton had stated his belief that all gases could be liquified by the use of low temperatures and/or high pressures. Faraday provided hard evidence for Dalton’s belief by applying pressure to liquefy chlorine gas and ammonia gas for the first time.

The ammonia liquefaction was of further interest, because Faraday observed that when he allowed the ammonia to evaporate again, it caused cooling.

The principle of cooling by artificial evaporation had been demonstrated publicly by William Cullen in Edinburgh in 1756. Cullen had used a pump to reduce the pressure above a flask of ether, causing the ether to evaporate quickly. The evaporation caused cooling, and ice formed on the outside of the flask as moisture from the air came into contact with it.

The importance of Faraday’s discovery was that he had shown that mechanical pumps could transform a gas at room temperature into a liquid. The liquid could then be evaporated, cooling its surroundings and the resulting gas could be collected and compressed by a pump into a liquid again, then the whole cycle could be repeated. This is the basis of how modern refrigerators and freezers work.

In 1862, Ferdinand Carré demonstrated the world’s first commercial ice-making machine at the Universal London Exhibition. The machine used ammonia as its coolant and produced ice at the rate of 200 kg per hour.

1825: Discovery of Benzene

Historically, benzene is one of the most important substances in chemistry, both in a practical sense – i.e. making new materials; and in a theoretical sense – i.e. understanding chemical bonding. Michael Faraday discovered benzene in the oily residue left behind from producing gas for lighting in London.

1831: Discovery of Electromagnetic Induction

This was an enormously important discovery for the future of both science and technology. Faraday discovered that a varying magnetic field caused electricity to flow in an electric circuit.

For example, moving a horseshoe magnet over a wire produces an electric current, because the movement of the magnet causes a varying magnetic field.

Previously, people had only been able to produce electric current with a battery. Now Faraday had shown that movement could be turned into electricity – or in more scientific language, kinetic energy could be converted to electrical energy.

Most of the power in our homes today is produced using this principle. Rotation (kinetic energy) is converted into electricity using electromagnetic induction. The rotation can be produced by high pressure steam from coal, gas, or nuclear energy turning turbines; or by hydroelectric plants; or by wind-turbines, for example.

1834: Faraday’s Laws of Electrolysis

Faraday was one of the major players in the founding of the new science of electrochemistry. This is the science of understanding what happens at the interface of an electrode with an ionic substance. Electrochemistry is the science that has produced the Li ion batteries and metal hydride batteries capable of powering modern mobile technology. Faraday’s laws are vital to our understanding of electrode reactions:

1836: Invention of the Faraday Cage

Faraday discovered that when an electrical conductor becomes charged, all of the extra charge sits on the outside of the conductor. This means that the extra charge does not appear on the inside of a room or cage made of metal.

The image at the top of this page has a man wearing a Faraday Suit – which has a metallic lining – keeping him safe from the electricity outside his suit.

In addition to offering protection for people, sensitive electrical or electrochemical experiments can be placed inside a Faraday Cage to prevent interference from external electrical activity.

Faraday cages can also create dead zones for mobile communications

1845: Discovery of the Faraday Effect – a magneto-optical effect

This was another vital experiment in the history of science, the first to link electromagnetism and light – a link finally described fully by James Clerk Maxwell’s equations in 1864, which established that light is an electromagnetic wave.

Faraday discovered that a magnetic field causes the plane of light polarization to rotate.

1845: Discovery of Diamagnetism as a Property of all Matter

Most people are familiar with ferromagnetism – the type shown by normal magnets. Faraday discovered that all substances are diamagnetic – most are weakly so – some are strongly so.

Diamagnetism opposes the direction of an applied magnetic field.

For example, if you held the north pole of a magnet near a strongly diamagnetic substance, this substance would be pushed away by the magnet.

Diamagnetism in materials, induced by very strong modern magnets, can be used to produce levitation – famously even living things, such as frogs are diamagnetic – and so can be levitated in a strong magnetic field.

The End

Michael Faraday died in London, aged 75, on August 25, 1867. He was survived by his wife Sarah. They had no children. He had been a devout Christian all of his life, belonging to a small branch of the religion called Sandemanians.

During his life, he had been offered burial in Westminster Abbey along with Britain’s kings and queens and scientists of the stature of Isaac Newton. He turned this down, in favor of a more modest end. His grave, where Sarah is also buried, can still be seen in London’s Highgate Cemetery

Robert Hooke

Robert Hooke

Early Life and Education

Robert Hooke was born on the Isle of Wight, England on July 28, 1635. His parents were John Hooke and Cecily Gyles. He was the youngest of their four children. For a large part of his childhood, and whole life, Robert Hooke’s health was delicate. He spent much of his school time at home.

As a young boy, he impressed his clergyman father with his fine skills in drawing and his work on instruments such as clocks. His father believed his son was destined to become a clockmaker or an artist.

In 1648, Robert Hooke’s father died, leaving him a legacy of 40 pounds – a significant amount of money. The 13-year-old boy traveled to London to be educated at Westminster School, where he learned the classical languages of Greek and Latin and studied mathematics and mechanics.

In 1653, aged 18, he enrolled at the University of Oxford’s Christ Church College, where he studied experimental science and became a chorister.

Aged 20, in 1655, Hooke’s career took a further turn towards science.

His abilities in working with mechanical instruments had become very refined, and he secured work in Oxford as an assistant to one of the founders of modern chemistry – Robert Boyle. Hooke worked with Boyle for seven years; during this time Boyle discovered Boyle’s Law using air pumps designed and built largely by Hooke.

In 1662, now aged 27, Hooke was appointed as Curator of Experiments for the newly founded Royal Society, whose purpose was to advance scientific understanding of the world.

As Curator, he was responsible for the experiments conducted by the Society. This was an important position for such a young man to hold. Clearly Hooke’s time with Boyle had won him admiration in the scientific world.

Hooke moved from Oxford to London, where he held the Curator position for forty years.

Robert Hooke’s Scientific Discoveries

The Measurement of Time

In about 1657, Hooke greatly improved the pendulum clock by inventing the anchor escapement. This was a cog which gave a small push to every swing a pendulum took, preventing it running down, while also moving the hands of the clock forward.

In about 1660, Hooke invented the balance spring, vital for accurate timekeeping in pocket watches, one of which he made for his own use. A pendulum cannot be used in a pocket watch, so another way of marking the passage of time is needed.

Hooke’s balance spring was attached to a balance wheel and produced a regular oscillation; this oscillation allowed time to be kept accurately. Christiaan Huygens invented the balance spring independently of Hooke over a decade later.

In 1660 Hooke discovered Hooke’s Law, which states that the tension force in a spring increases in direct proportion to the length it is stretched to.

Micrographia and Microscopy

In 1665, when he was aged 30, Hooke published the first ever scientific bestseller: Micrographia.

The book was a showcase for Hooke’s particular talents – his understanding of nature and light, his highly developed skills in designing and constructing scientific instruments, and his skills as an artist.

Hooke had built a compound microscope with a new, screw-operated focusing mechanism he had designed. Previously, people needed to move the specimen to get it in focus.

He further improved the microscope with lighting. He placed a water-lens beside the microscope to focus light from an oil-lamp on to his specimens to illuminate them brightly.

Alexander Fleming

Alexander Fleming

Scottish biologist and inventor Alexander Firming is widely regarded for his 1928 discovery of penicillin, a drug that is used to kill harmful bacteria. His work on immunology, bacteriology, and chemotherapy is considered groundbreaking and highly influential.

Early Life and Education:

Born in Ayrshire, Scotland on August 6, 1881 to Hugh Fleming and Grace Stirling Morton, Alexander Fleming was the third of the four children. He attended medical school in London, England and graduated in 1906. Fleming assisted in battlefield hospitals in France during World War I (1911-1918), where he observed that some soldiers, despite surviving their initial battlefield wounds, were dying of septicemia or some another infection only after a few years.

Contributions and Achievements:

Once the war was over, Fleming looked for medicines that would heal infections. The antiseptics of World War I were not totally efficient, and they primarily worked on a wound’s surface. Spraying an antiseptic made things even worse if the wound was deep.

Fleming came back to his laboratory in 1928 after a long vacation. He carried out an experiment and left several dishes with several bacteria cultures growing in them. After some time, he observed that some of the dishes were contaminated with a fungus, which ruined his experiment. He was about to discard the dishes, but he noticed that in one dish, the bacteria failed to grow in an area around the fungus.

He successfully isolated the fungus and established it was from the Penicillium group or genus. Fleming made his discovery public in 1929, however to a mixed reaction. While a few doctors thought penicillin, the antibiotic obtained from the Penicillium fungus, might have some importance as a topical antiseptic, the others were skeptical. Fleming was sure that the penicillin could also function inside the body. He performed some experiments to demonstrate that the genus of fungus had germ-killing power, even when it was diluted 800 times. Fleming tried to cultivate penicillin until 1940, but it was hard to grow, and isolating the germ-killing agent was even harder. He was unsure if it would ever work in a proper manner.

Luckily, a German Chemist, Ernst Chain, discovered the process to isolate and concentrate the germ-killing agent in penicillin some time later. Another Australian pharmacologist Howard Florey found out the ways of its mass production. During World War I, the goverments of U.S. and Great Britain funded Florey and Chain, therefore the penicillin almost became the magic spell that cured many diseases. Florey and Chain were awarded the Nobel Prize in 1945.

Personal Life and Death:

Fleming married his first wife, Sarah, who died in 1949. Their only child, Robert Fleming, went on to become a general medical practitioner. Fleming married for the second time to Dr. Amalia Koutsouri-Vourekas, with whom he worked at St. Mary’s, on 9 April 1953. She also died in 1986.

Fleming died of a heart failure in London in 1955.