Thomas Alva Edison was born in 1847 in Milan, Ohio. When he was seven, his family moved to Port Huron, Michigan where he remained until he struck out on his own at the age of sixteen. Edison had very little formal education as a child, and was taught at home by his mother the basics in reading, writing and arithmetic. Because of his curiosity he became a voracious reader and at the age of 10, he set up a laboratory in his basement.

Edison began work at age thirteen as a newsboy, and spent much of his free time reading scientific and technical books. He also learned how to operate a telegraph and by the time he was sixteen he was working as a telegrapher full time.

The development of the telegraph was revolutionary in the field of communications. Edison's involvement with this industry allowed him to travel, see the country and gain experience. He worked in several cities before arriving in Boston in 1868. It was at this time that Edison changed his profession from telegrapher to inventor. His first patented invention, an electric vote recorder to be used in congress, was a commercial failure, and he decided that in the future that he would only invent things he was sure that the public would want.

Edison later moved to New York City, and within a year was able to open a workshop in Newark, New Jersey. He was a poor financial manager and by 1875 he began to experience financial problems. Edison asked his father to help him build a new laboratory and machine shop in Menlo Park, New Jersey, and with two associates Charles Batchelor and John Kruesi, Edison achieved his greatest successes in the laboratory and was called the "Wizard of Menlo Park." This research and development laboratory was the first of its kind anywhere; it became a model for later, modern research and development facilities such as Bell Laboratories. It was during this period of his life that Edison and his staff were responsible for many inventions and innovations. More patents were issued to Edison than have been issued to any other single person in United States history, a total of 1,093.

In 1878-1879, Edison worked on the development of a practical incandescent electric light. The concept of electric lighting was being studied by many different inventors, however prior to Edison, no one had invented an incandescent bulb practical for home use. Edison not only invented an incandescent bulb, but also an electric lighting system that contained all the elements necessary to make the incandescent light practical, safe, and economical. Edison searched for the proper "filament" or wire, which when light flowed through it would give good light. He sent people to the jungles of the Amazon and the forests of Japan in his search for the perfect filament material. Edison tested over 6,000 plants, among them were baywood, boxwood, hickory, cedar, flax, bamboo and others. After one and a half years, $40,000, and performing 1,200 experiments, he succeeded. His incandescent lamp, with a filament of carbonized sewing thread, was considered to be a success as it burned for thirteen and one half hours. In December of 1879, Edison's public demonstration of his incandescent lighting system occurred when he lighted the entire Menlo Park laboratory complex.

Thomas Alva Edison died when he was 84 years old, on Sunday, October 18, 1931. He was still experimenting up until the time he died.

albert einstein
Albert Einstein is undoubtedly one of the most fascinating and influential figures of the modern era. As a preeminent physicist, he radically transformed our understanding of the universe. As an ardent humanist, he took an active and outspoken stance on the significant political and social issues of his time. As a committed Jew, he advocated a distinctive moral role for the Jewish people.

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 Albert Einstein's contribution to modern physics is simply unique. His scientific career was a constant quest for the universal and immutable laws which govern the physical world. His theories spanned the fundamental questions of nature, from the very large to the very small, from the cosmos to sub-atomic particles. He overturned the established concepts of time and space, energy and matter. Einstein played a crucial role in establishing the two pillars of 20th century physics: he was the father of the theory of relativity and a major contributor to quantum theory.

Einstein was a theoretical physicist - his only concrete tools being pencil and paper. It has been said that his true tools were a penetrating and intuitive grasp of the workings of the natural world and the "thought experiment" - an intellectual exercise used by physicists to reach a theoretical conclusion from idealized physical processes. Yet, Einstein was not a purely abstract thinker. He grasped the world in concrete images and strove to translate them into words and equations that could be understood by others.

Science was Albert Einstein's first love, yet he always found time to devote tireless efforts to political causes close to his heart. His ardent humanism led him to strive for peace, freedom and social justice. The young Einstein found the authoritarianism and militarism of the German educational system profoundly disturbing. The virulent nationalism and brutality of the First World War served to confirm Einstein's pacifist and internationalist convictions.
In the 1920s, Einstein became an active leader of the international anti-war movement and supported conscientious objection. However, the Nazi rise to power brought about a substantial change in Einstein's position: he began to advocate military preparedness by the European democracies against the threat of Nazism. In this context, Einstein wrote his famous letter to U.S. President Roosevelt in which he urged him to initiate an American nuclear research programme. With the onset of the atomic era, Einstein realized that nuclear weapons were a profound risk to humanity and could bring an end to civilization. During the last decade of his life, he was tireless in his efforts to create effective international cooperation to prevent war.

Throughout his life, Albert Einstein felt a close affinity with the Jewish people. Einstein defined Judaism as a culture with a shared historical past and common ethical values rather than as an institutionalized religion. For him the main values of Judaism were intellectual aspiration and the pursuit of social justice. Like Spinoza, he did not believe in a personal god, but that the divine reveals itself in the physical world. Einstein supported the creation of a homeland for the Jews in Palestine. However, he stipulated that any solution of the Arab-Jewish conflict had to be based on mutual understanding and constent.

Albert Einstein was one of the founders of the Hebrew University of Jerusalem. He served on the University's first Board of Governors and Academic Council. He delivered the University's inaugural scientific lecture and edited its first collection of scientific papers. His unique relationship to this institution found a lasting expression in the bequest of his literary estate and personal papers to the Hebrew University in his Last Will and Testament.

friedrich wilhelm herschel
Friedrich Wilhelm Herschel was born on November 15th 1738 in Hannover, Germany. His father was a military musician and each of his five children was taught to play a musical instrument. From 1753 until 1773, Herschel's career was that of a musician, and he belonged to a military music orchestra, was a church organist, and taught students music from his home. In 1773 his interest in astronomy suddenly grew and he read books on astronomy and bought instruments and lenses. Herschel's first telescope was a small reflecting telescope that did not satisfy him for long, so he decided to make a bigger instrument. Good mirrors and lenses were too expensive, so Herschel bought equipment from a man in Bath for pouring metal for the mirrors, and tools for grinding and polishing the mirrors so that he could construct more powerful reflecting telescopes. William's sister Caroline lived with him and assisted him in making his mirrors.

In 1779 while living in Bath, he was asked to join the Royal Society. Between 1779 and 1781 he measured the heights of about one hundred mountains on the moon, carefully recorded the data and prepared papers that were presented to the Royal Society.

On the evening of March 13th, 1781 Herschel discovered a bright object in an area of the sky where there was supposed to be no star. He suspected that it was a comet, and further observations revealed a slowly moving object. After additional studies and calculations it was determined that a new planet was formed. Herschel named the newly discovered planet "Georgium sidus", or George's star after King George III. Later the name Uranus was proposed by Galle in Berlin and was used by most astronomers.

In November 1781, Herschel went to London and received the Copley medal from Sir Joseph Banks of the Royal Society. At the end of May 1782, Herschel was invited to London by King George III. He showed the royal family several planets during June and July and was offered the position of court astronomer at Windsor. His travels and experimental work was not covered by the salary he received for being the Royal astronomer, so Herschel began to build and sell telescopes. The high quality of his optics was soon widely known outside of England and he received many orders from foreign countries.

Between 1786 and 1802, Herschel published three catalogues containing data on 2500 heavenly objects. These observations were conducted with a telescope he constructed, which had a focal length of 20 feet and a diameter of 18.8 inches. It was with this telescope that he discovered the Uranus moons of Titania and Oberon. He later built another telescope with a 40-foot focal length, and a diameter of 48 inches. It was not his favorite, because the mirror needed re-polishing very often and the tube was heavy and difficult to handle. However with this telescope Herschel did discover the sixth and seventh moons of Saturn, Enceladus and Mimas. Herschel continued making observations and cataloging his discoveries until his death in 1822 at age 84.

antonie van leeuwenhoek
Leeuwenhoek was born in Delft, Holland on October 24, 1632. His father was a basket-maker, and although Leeuwenhoek did not receive a university education and was not considered a scholar, his curiosity and skill allowed him to make some of the most important discoveries in the history of Biology.

He was educated as a child in the town of Warmond, lived with his uncle in Benthuizen, and apprenticed in 1648 as a fabric merchant. He returned to Delft, and established his own business as a fabric merchant, but also worked as a surveyor, a wine assayer and as a city official.

At some time before 1668, Antonie van Leeuwenhoek learned to grind lenses, and used these to make very simple hand-held microscopes. These microscopes were not compound microscopes made of two or more lenses but refined magnifying glasses made with finely ground lenses. These microscopes, with appropriate lighting, allowed him to magnify objects over 275 times. His curiosity about this microscopic world and his diligence in recording his observations allowed him to share with others what he had seen with his microscopes.

Leeuwenhoek hired an illustrator to draw what he saw and he wrote explicit descriptions of the microorganisms he saw through his microscopes. He studied Protists, plant cells, various types of algae, and was the first person to view bacteria, which he termed "animalcules". Leeuwenhoek discovered these bacteria while viewing scrapings from his teeth and the teeth of others. He also discovered blood cells and was the first to see living sperm cells in animals.

For fifty years, Leeuwenhoek wrote letters to the Royal Society of London, in which he described his findings. His letters concerning these discoveries became so famous that they were published and translated into many other languages. In 1680 he was elected a full member of the Royal Society, which was normally reserved for scientific scholars. He died on August 30, 1723 but has since been recognized as one of the most important scientists of the day.

Leeuwenhoek Microscopes - Leeuwenhoek designed and built several hundred microscopes that were all very small and had a very similar design and function. The dimensions of his microscopes were fairly constant at approximately two inches long and one inch across. The main body of these microscopes consists of two flat and thin metal (usually brass) plates riveted together. Sandwiched between the plates was a small bi-convex lens capable of magnifications ranging from 70x to over 250x, depending upon the lens quality.

sir isaac newton
Sir Isaac Newton, who was ironically born the same year that Galileo died, is popularly known as one of history's greatest scientists. Many of his discoveries and theories in the areas of light, color, and optics form the basis for current scientific thought in these disciplines. In addition to his extensive work in optics, Newton is perhaps best known for his theory of universal gravitation. He also is considered one of the inventors of calculus along with German mathematician Gottfried Willhelm von Leibniz. Newton's three laws of motion are considered basic to any physics student's education. Newton, like Galileo, owed the formation of several of his discoveries to a period of self-study and scientific observation unencumbered by structured or formal education.

Newton is thought to have been born on Christmas day in 1642, a short time after the death of his father. His mother remarried, leaving him with his grandmother to be educated in Lincolnshire. Reports of his academic progress characterize Isaac as "idle" and "inattentive," which led to his being removed from school altogether by his mother. An uncle saw promise in Newton, prepared him for the university, and enrolled him at Trinity College, Cambridge, in 1661. While at Trinity, Newton studied philosophy, mathematics, mechanics, astronomy, and law.

In 1665, Newton's studies were interrupted by the closure of Trinity College because of an outbreak of plague. It was during this time, ironically, that Newton's scientific gift emerged. Newton returned to his home in Lincolnshire and in two years put forth innovative theories in mathematics, optics, physics, and astronomy. In 1667, when the college reopened, Newton was offered a position as Lucasian Professor at the age of 27. His first work in this position was on optics. Newton had been grinding his own lenses for several years in an effort to produce an improved telescope. His lens making activities led him to notice a problem with chromatic aberration. His attempt to solve this problem resulted in the development of the reflecting telescope. Newton also concluded that white light is a blend of colors that can be observed when light is passed through a prism.

During the period 1665-1669, Newton developed his "method of fluxions" which served to unify mathematical techniques and led to the 1666 development of calculus. In 1675 Leibniz, a German mathematician, employed the same method, which he termed differential calculus. Because he quickly published these results, Leibniz is acknowledged as the inventor of calculus. Newton was known to be wary of publishing because he was afraid of criticism, a character trait that left his work virtually unknown until 1672, when he published his first paper on light and color in the Royal Society's Philosophical Transactions of the Royal Society. This work formed the basis of his 1704 treatise, "Opticks" that explained, among other things, his experiments to reduce chromatic aberration and described the reflecting telescope. Up until his death in 1727, Newton claimed that he alone had invented calculus and accused Leibniz of plagiarism, a difficult assertion to prove since he had virtually isolated himself in Cambridge until 1684.

Newton's interest in astronomy was reinvigorated by a visit from Edmund Halley, the British astronomer best known as the namesake of Halley's Comet. This visit prompted Newton to pursue his theories of mechanics, which became the basis for his three laws of motion. His theories were published in 1687. Not only did this represent a new science, but it also placed Newton in the forefront of scientific debate and controversy. After the publication of "The Principia", Newton was accused of plagiarism by Robert Hooke, an accusation that was never proved, but ironically put Newton in a similar position to Leibniz.

After this prolific period of scientific observation, experimentation, and discovery, Isaac Newton spent the rest of his life as a government official living in London, after suffering a nervous breakdown in 1693. In 1703, Newton was elected President of the Royal Society, and in 1708 was the first scientist to be honored for his work with a knighthood. Newton died in 1727. Of his funeral, the French philosopher Voltaire said "in a country where mortals are canonized, his discoveries might very well pass for miracles."