Title: History of physics
Content:  The late 17th and early 18th centuries saw the achievements of Cambridge University physicist and mathematician Sir Isaac Newton (1642-1727). Newton, a fellow of the Royal Society of England, combined his own discoveries in mechanics and astronomy to earlier ones to create a single system for describing the workings of the universe. Newton formulated three laws of motion which formulated the relationship between motion and objects and also the law of universal gravitation, the latter of which could be used to explain the behavior not only of falling bodies on the earth but also planets and other celestial bodies. To arrive at his results, Newton invented 
Title: Annus mirabilis
Content:  In 1666 Isaac Newton, aged 23, made revolutionary inventions and discoveries in calculus, motion, optics and gravitation. It was in this year that Newton was alleged to have observed an apple falling from a tree, and in which he in any case hit upon the law of universal gravitation (Newton's apple). He was afforded the time to work on his theories due to the closure of Cambridge University by an outbreak of plague.
Title: Isaac Newton
Content:  Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, theologian, and author (described in his time as a "natural philosopher") widely recognised as one of the greatest mathematicians and physicists of all time and among the most influential scientists. He was a key figure in the philosophical revolution known as the Enlightenment. His book Philosophiæ Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), first published in 1687, established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus. In Principia, Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint until it was superseded by the theory 
Title: 1668 in science
Content: Isaac Newton invents the reflecting telescope. 
Title: East Midlands
Content:  Isaac Newton, born in Grantham in 1642, is perhaps the most prolific scientist. His accomplishments include calculus, Newton's laws of motion, and Newton's law of universal gravitation, among many others. There is a shopping centre named in his honour in Grantham. Thomas Simpson from Leicestershire is known for Simpson's rule. Roger Cotes invented the concept of the radian in 1714, but the term was not so-named until 1873. Henry Cavendish, loosely connected with Derbyshire, discovered hydrogen in 1766 (although the element's name came from Antoine Lavoisier), and Cavendish was the first to estimate an accurate mass of the Earth in 1798 in his Cavendish experiment. The Cavendish Laboratory at the University of Cambridge 
Title: History of classical mechanics
Content:  Western Europe. He formulated the conservation law for elastic collisions, produced the first theorems of centripetal force, and developed the dynamical theory of oscillating systems. He also made improvements to the telescope, discovered Saturn's moon Titan, and invented the pendulum clock. His wave theory of light, published in Traite de la Lumiere, was later adopted by Fresnel in the form of the Huygens-Fresnel principle. Sir Isaac Newton was the first to unify the three laws of motion (the law of inertia, his second law mentioned above, and the law of action and reaction), and to prove that these laws govern 
Title: History of science
Content:  In 1687, Isaac Newton published the Principia Mathematica, detailing two comprehensive and successful physical theories: Newton's laws of motion, which led to classical mechanics; and Newton's law of universal gravitation, which describes the fundamental force of gravity.
Title: Early life of Isaac Newton
Content:  are now almost universally rejected, his investigations led to discoveries which are of permanent value. He succeeded in explaining the colour of thin and of thick plates (diffraction), and the inflexion of light, and he wrote on double refraction, light polarisation and binocular vision. He also invented a reflecting quadrant for observing the angles between the moon and the fixed stars&mdash; the same in every essential as the historically important navigational instrument more commonly known as Hadley's quadrant. This discovery was communicated by him to Edmund Halley in 1700 but was not published, or communicated to the Royal Society, until after Newton's death, when a description of it was found among his papers.
Title: Scientific Revolution
Content:  first one to correctly formulate laws concerning centrifugal force and discovered the theory of the pendulum) and optics (being one of the most influential proponents of the wave theory of light). ; Isaac Newton (1643–1727) built upon the work of Kepler, Galileo and Huygens. He showed that an inverse square law for gravity explained the elliptical orbits of the planets, and advanced the law of universal gravitation. His development of infinitesimal calculus (along with Leibniz) opened up new applications of the methods of mathematics to science. Newton taught that scientific theory should be coupled with rigorous experimentation, which became the keystone of modern science. People and key ideas that emerged from the 16th and 17th centuries:
Title: What the Stuarts Did for Us
Content: Experimental science was introduced by the Lord Chancellor Francis Bacon who died inventing the frozen chicken. ; Properties of gases investigated by Robert Boyle and Richard Towneley led to Denis Papin's invention of the pressure cooker. ; The steam engine was invented by Thomas Newcomen to drain water from the coalmines of the Midlands. ; The pendulum clock based on Galileo's principles was invented by Christiaan Huygens and led to the establishment of GMT. ; Principia by Isaac Newton established three simple laws that revolutionised our view of the universe. "Before Stuart times the man who really ruled the scientific roost was the Greek philosopher Aristotle, even if he had been dead for 2000 years. But by the 1600s his ideas were becoming discredited and the Stuarts needed a new approach to understanding nature." - Adam Hart-Davis Hart-Davis travels around Britain to introduce the idea and inventions of the Stuart Period in science and engineering. 

Question: what was sir isaac newton's inventions?
Answer: Reflecting telescope.