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Opticks
Before Newton completed his masterpiece, The Principia Mathematica, he had established his reputation with this treatise on the properties of light. Though on a narrower topic, this work is as impressive in its own right as The Principia, for it provided a scientific analysis of light that became the basis of our modern understanding. Based on experiments in which a beam of light was passed through a prism, Newton showed that white light was complex and could be analyzed as a blend of the various colors of the spectrum. Divided into three books, the first describes his experiments with the spectrum. The second deals with the ring phenomenon, in which concentric rings of colors appear in the thin layer of air separating a lens and an underlying plate of glass. The third book describes his work on diffraction. Also discussed is Newton's theory that light consists basically of "material corpuscles" in motion.Though clearly intended for fellow scientists this classic monument of modern physics is surprisingly readable and understandable for nonspecialists.
414 pages, Paperback
First published January 1, 1704
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About the author
Isaac Newton
949 books870 followersSir Isaac Newton, FRS , was an English physicist, mathematician, astronomer, natural philosopher, and alchemist. His Philosophiæ Naturalis Principia Mathematica, published in 1687, is considered to be the most influential book in the history of science. In this work, Newton described universal gravitation and the three laws of motion, laying the groundwork for classical mechanics, which dominated the scientific view of the physical universe for the next three centuries and is the basis for modern engineering. Newton showed that the motions of objects on Earth and of celestial bodies are governed by the same set of natural laws by demonstrating the consistency between Kepler's laws of planetary motion and his theory of gravitation, thus removing the last doubts about heliocentrism and advancing the scientific revolution.
In mechanics, Newton enunciated the principles of conservation of momentum and angular momentum. In optics, he invented the reflecting telescope and developed a theory of colour based on the observation that a prism decomposes white light into a visible spectrum. He also formulated an empirical law of cooling and studied the speed of sound.
In mathematics, Newton shares the credit with Gottfried Leibniz for the development of the differential and integral calculus. He also demonstrated the generalised binomial theorem, developed the so-called "Newton's method" for approximating the zeroes of a function, and contributed to the study of power series.
Newton was also highly religious (though unorthodox), producing more work on Biblical hermeneutics than the natural science he is remembered for today.
In a 2005 poll of the Royal Society asking who had the greater effect on the history of science, Newton was deemed much more influential than Albert Einstein.
In mechanics, Newton enunciated the principles of conservation of momentum and angular momentum. In optics, he invented the reflecting telescope and developed a theory of colour based on the observation that a prism decomposes white light into a visible spectrum. He also formulated an empirical law of cooling and studied the speed of sound.
In mathematics, Newton shares the credit with Gottfried Leibniz for the development of the differential and integral calculus. He also demonstrated the generalised binomial theorem, developed the so-called "Newton's method" for approximating the zeroes of a function, and contributed to the study of power series.
Newton was also highly religious (though unorthodox), producing more work on Biblical hermeneutics than the natural science he is remembered for today.
In a 2005 poll of the Royal Society asking who had the greater effect on the history of science, Newton was deemed much more influential than Albert Einstein.
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Displaying 1 - 18 of 18 reviews
September 16, 2019
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___________________________
I’ve long wanted to read Newton’s Principia, but its reputation intimidates me. Everyone seems to agree that it is intensely difficult, and I’m sorry to say I haven’t worked up enough nerve to face it yet. But I did still want to read Newton; so as soon as I learned about this book, Newton’s more popular and accessible volume, I snatched it up and happily dug in.
The majority of this text is given over to descriptions of experiments. To the modern reader—and I suspect to the historical reader as well—these sections are remarkably dry. In simple yet exact language, Newton painstakingly describes the setup and results of experiment after experiment, most of them conducted in his darkened chamber, with the window covered up except for a small opening to let in the sunlight. Yet even if this doesn’t make for a thrilling read, it is impossible not to be astounded at the depth of care, the keenness of observation, and the subtle brilliance Newton displays. Using the most basic equipment (his most advanced tool is the prism), Newton tweezes light apart, making an enormous contribution both to experimental science and to the field of optics.
At the time, the discovery that white light could be decomposed into a rainbow of colors, and that this rainbow could be recombined back into white light, must have seemed as momentous as the discovery of the Higgs Boson. And indeed, even the modern reader might catch a glimpse of this excitement as she watches Newton carefully set up his prism in front of his beam of light, tweaking every variable, adjusting every parameter, measuring everything could be measured, and describing in elegant prose everything that couldn’t.
Because I had recently read Feynman’s QED, one thing in particular caught my attention. Here’s the problem: When you have one surface of glass, even if most of the light passes through it, some of the light is reflected; and you can roughly gauge what portion of light does one or the other. Let’s say on a typical surface of glass, 4% of light is reflected. Now we add another surface of glass behind the first. According to common sense, 8% of the light should be reflected, right? Wrong. Now the amount of light which is reflected varies between 0% and 16%, depending on the distance between the two surfaces. This is truly bizarre; for it seems that the mere presence of second surface of glass alters the reflectiveness of the first. But how does the light “know” there is a second surface of glass? It seems the light somehow is affected before it comes into contact with either surface.
Well, Newton was aware of this awkward problem. He famously comes up with his theory of “fits of easy reflection or transmission” to explain this phenomenon. But this “theory” was merely to say that the glass, for some unknown reason, sometimes lets light through, and sometimes reflects it. In other words, it was hardly a theory at all.
Also fascinating to the modern reader is the strange dual conception of light as waves and as particles in this work, which can't help but remind us of the quantum view. The wave theory makes it easy to account for the different refrangibility of the different colors of light (i.e. the different colors reflect at different angles in a prism).
Yet to this notion of vibrations, Newton adds the "corpuscular" theory of light, which held (in opposition to his contemporary, Christiaan Huygens) that light was composed of small particles. This theory must have been attractive to Newton because it fit into his previous work in physics. It explained why beams of light, like other solid bodies, travel in straight lines (cf. Newton's first law), and reflect off surfaces at angles equal to their angles of incidence (cf. Newton's third law).
As a side note, despite some problems with the corpuscular theory of light, it came to be accepted for a long while, until the phenomenon of interference gave seemingly decisive weight to the wave theory. (Light, like water waves, will interfere with itself, creating characteristic patterns; cf. the famous double-slit experiment.) The wave theory was reinforced with Maxwell's equations, which treated light as just another electro-magnetic wave. It was, in fact, Einstein who brought back the viability of the corpuscular theory, when he suggested the idea that light might come in packets to explain the photoelectric effect. (Blue light, when shined on certain metals, will cause an electric current, while red light won't. Why not?)
All this tinkering with light is good fun, especially if you’re a physicist (which I’m not). But the real treat, at least for the layreader, comes at the final section, where Newton speculates on many of the unsolved scientific problems of his day. His mind is roving and vast; and even if most of his speculations have turned out incorrect, it’s stunning to simply witness him at work. For example, Newton realizes that radiation can travel without a medium (like air), and can heat objects even in a vacuum. (And thank goodness for that, for how else would the earth be warmed by the sun?) But from this fact he incorrectly deduces that there must be some more subtle medium that remains (like the famous ether).
Yet for all Newton's perspicacity, the most touching section was a list of question Newton asks, as if to himself, that he cannot hope to answer. It seems that even the most brilliant among us are stunned into silence by the vast mystery of the cosmos.
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___________________________
My Design in this Book is not to explain the Properties of Light by Hypotheses, but to propose and prove them by Reason and Experiment
I’ve long wanted to read Newton’s Principia, but its reputation intimidates me. Everyone seems to agree that it is intensely difficult, and I’m sorry to say I haven’t worked up enough nerve to face it yet. But I did still want to read Newton; so as soon as I learned about this book, Newton’s more popular and accessible volume, I snatched it up and happily dug in.
The majority of this text is given over to descriptions of experiments. To the modern reader—and I suspect to the historical reader as well—these sections are remarkably dry. In simple yet exact language, Newton painstakingly describes the setup and results of experiment after experiment, most of them conducted in his darkened chamber, with the window covered up except for a small opening to let in the sunlight. Yet even if this doesn’t make for a thrilling read, it is impossible not to be astounded at the depth of care, the keenness of observation, and the subtle brilliance Newton displays. Using the most basic equipment (his most advanced tool is the prism), Newton tweezes light apart, making an enormous contribution both to experimental science and to the field of optics.
At the time, the discovery that white light could be decomposed into a rainbow of colors, and that this rainbow could be recombined back into white light, must have seemed as momentous as the discovery of the Higgs Boson. And indeed, even the modern reader might catch a glimpse of this excitement as she watches Newton carefully set up his prism in front of his beam of light, tweaking every variable, adjusting every parameter, measuring everything could be measured, and describing in elegant prose everything that couldn’t.
Whence it follows, that the colorifick Dispositions of Rays are also connate with them, and immutable; and by consequence, that all the Productions and Appearances of Colours in the World are derived, not from any physical Change caused in Light by Refraction or Reflexion, but only from the various Mixtures or Separations of Rays, by virtue of their different Refrangibility or Reflexibility. And in this respect the Science of Colours becomes a Speculation as truly mathematical as any other part of Opticks.
Because I had recently read Feynman’s QED, one thing in particular caught my attention. Here’s the problem: When you have one surface of glass, even if most of the light passes through it, some of the light is reflected; and you can roughly gauge what portion of light does one or the other. Let’s say on a typical surface of glass, 4% of light is reflected. Now we add another surface of glass behind the first. According to common sense, 8% of the light should be reflected, right? Wrong. Now the amount of light which is reflected varies between 0% and 16%, depending on the distance between the two surfaces. This is truly bizarre; for it seems that the mere presence of second surface of glass alters the reflectiveness of the first. But how does the light “know” there is a second surface of glass? It seems the light somehow is affected before it comes into contact with either surface.
Well, Newton was aware of this awkward problem. He famously comes up with his theory of “fits of easy reflection or transmission” to explain this phenomenon. But this “theory” was merely to say that the glass, for some unknown reason, sometimes lets light through, and sometimes reflects it. In other words, it was hardly a theory at all.
Every Ray of Light in its passage through any refracting Surface is put into a certain transient Constitution or State, which in the progress of the Ray returns at equal Intervals, and disposes the Ray at every return to be easily transmitted through the next refracting Surface, and between the returns to be easily reflected by it.
Also fascinating to the modern reader is the strange dual conception of light as waves and as particles in this work, which can't help but remind us of the quantum view. The wave theory makes it easy to account for the different refrangibility of the different colors of light (i.e. the different colors reflect at different angles in a prism).
Do not several sorts of Rays make Vibrations of several bignesses, which according to their bignesses excite Sensations of several Colours, much after the manner that the Vibrations of the Air, according to their several bignesses excite Sensations of several sounds. And particularly do not the most refrangible Rays excite the shortest Vibrations for making a Sensation of deep violet, the least refrangible the largest for making a Sensation of deep red, and the several intermediate bignesses to make Sensations of the several intermediate Colours?
Yet to this notion of vibrations, Newton adds the "corpuscular" theory of light, which held (in opposition to his contemporary, Christiaan Huygens) that light was composed of small particles. This theory must have been attractive to Newton because it fit into his previous work in physics. It explained why beams of light, like other solid bodies, travel in straight lines (cf. Newton's first law), and reflect off surfaces at angles equal to their angles of incidence (cf. Newton's third law).
Are not the Rays of Light very small Bodies emitted from shining Substances? For such Bodies will pass through uniform Mediums in right Lines without bending into the shadow, which is the Nature of the Rays of Light. They will also be capable of several Properties, and be able to conserve their Properties unchanged in passing through several Mediums, which is another conditions of the Rays of Light.
As a side note, despite some problems with the corpuscular theory of light, it came to be accepted for a long while, until the phenomenon of interference gave seemingly decisive weight to the wave theory. (Light, like water waves, will interfere with itself, creating characteristic patterns; cf. the famous double-slit experiment.) The wave theory was reinforced with Maxwell's equations, which treated light as just another electro-magnetic wave. It was, in fact, Einstein who brought back the viability of the corpuscular theory, when he suggested the idea that light might come in packets to explain the photoelectric effect. (Blue light, when shined on certain metals, will cause an electric current, while red light won't. Why not?)
All this tinkering with light is good fun, especially if you’re a physicist (which I’m not). But the real treat, at least for the layreader, comes at the final section, where Newton speculates on many of the unsolved scientific problems of his day. His mind is roving and vast; and even if most of his speculations have turned out incorrect, it’s stunning to simply witness him at work. For example, Newton realizes that radiation can travel without a medium (like air), and can heat objects even in a vacuum. (And thank goodness for that, for how else would the earth be warmed by the sun?) But from this fact he incorrectly deduces that there must be some more subtle medium that remains (like the famous ether).
If in two large tall cylindrical Vessels of Glass inverted, to little Thermometers be suspended so as not to touch the Vessels, and the Air be drawn out of one of these Vessels thus prepared be carried out of a cold place into a warm one; the Thermometer in vacuo will grow warm as much, and almost as soon as the Thermometer that is not in vacuo. And when the Vessels are carried back into the cold place, the Thermometer in vacuo will grow cold almost as soon as the other Thermometer. Is not the Heat of the warm Room convey’d through the Vacuum by the Vibrations of a much subtiler Medium than Air, which after the Air was drawn out remained in the Vacuum?
Yet for all Newton's perspicacity, the most touching section was a list of question Newton asks, as if to himself, that he cannot hope to answer. It seems that even the most brilliant among us are stunned into silence by the vast mystery of the cosmos.
What is there in places almost empty of Matter, and whence is it that the Sun and Planets gravitate towards one another, without dense Matter between them? Whence is it that Nature doth nothing in vain; and whence arises all that Order and Beauty which we see in the World? To what end are Comets, and whence is it that Planets move all one and the same way in Orbs concentrick, while Comets move all manner of ways in Orbs very excentrick; and what hinders the fix’d Stars from falling upon one another? How came the Bodies of animals to be contrived with so much Art, and for what ends were their several Parts? Was the Eye contrived without Skill in Opticks, and the Ear without Knowledge of Sounds? How do the Motions of the Body follow from the Will, and whence is the Instinct in Animals?
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June 4, 2013Newton played with prisms and wrote about it. A lot. I did the same thing for a fifth grade science fair project but, yeah, his was better.
Opticks is supposed to be much more accessible than The Principia. Which it is, but it will still only appeal to the more meticulous, math-minded among us. Newton’s analysis of the properties of light have historical significance (specifically in regards to white light) and there were numerous equations which looked like they may mean something important. It’s Newton, so it’s a safe bet.
However, he also talks a bit about the impact of the aether and corpuscles of light. A nice reminder that even the best minds can flub it every once and awhile.
Overall, Opticks reminded me of Gilbert’s De Magnete. Gilbert conducted and recorded experiment after experiment with magnets; Newton did the same with light. It’s difficult for a layperson to fully appreciate the significance of this work in the time it was written so I’ll leave this unrated as well.
Opticks is supposed to be much more accessible than The Principia. Which it is, but it will still only appeal to the more meticulous, math-minded among us. Newton’s analysis of the properties of light have historical significance (specifically in regards to white light) and there were numerous equations which looked like they may mean something important. It’s Newton, so it’s a safe bet.
However, he also talks a bit about the impact of the aether and corpuscles of light. A nice reminder that even the best minds can flub it every once and awhile.
Overall, Opticks reminded me of Gilbert’s De Magnete. Gilbert conducted and recorded experiment after experiment with magnets; Newton did the same with light. It’s difficult for a layperson to fully appreciate the significance of this work in the time it was written so I’ll leave this unrated as well.
November 11, 2017
Last year, I did a self study in physics (using the very impressive and accessible works of Harvard's historian of science, Gerald Holton). The works I read referenced heavily to the works of Copernicus, Kepler, Galilei, Netwon and the like. It is in this frame of reference that I skimmed over Newton's Opticks.
One thing that surprised me was that, compared to Newton's Principia, Opticks is fairly accessible. I didn't delve into it though - knowing that Newton's thoughts have been updated since the 1920's (and in effect even earlier). I did read certain interesting passages and I was amazed by the clarity and precision of Newton: this is prototypical science, with clearly formulated hypotheses and careful expositions.
I plan to do a self study of mathematics in the (far) future, in order to grasp the subject of physics on a higher level. Maybe I will return to Netwon's Opticks at that time.
One thing that surprised me was that, compared to Newton's Principia, Opticks is fairly accessible. I didn't delve into it though - knowing that Newton's thoughts have been updated since the 1920's (and in effect even earlier). I did read certain interesting passages and I was amazed by the clarity and precision of Newton: this is prototypical science, with clearly formulated hypotheses and careful expositions.
I plan to do a self study of mathematics in the (far) future, in order to grasp the subject of physics on a higher level. Maybe I will return to Netwon's Opticks at that time.
August 20, 2024
Me gustó mucho más que los Principia, el lenguaje es más coloquial y accesible. También lo leí para una tesina que escribí para la facultad, en 2002.
December 25, 2022
Some months ago I started to seek out more work of great minds written 'from the horse's mouth.' This after reading 'The Autobiography of Ben Franklin.' What a treat. To have Ol' Ben describe in great detail his hopes and his setbacks has been a breakthrough read. To have these great minds reflect unvarnished, rather than through filters in the typical biography, is better insight into truth. Plus, I'm less interested in the story of their life, rather more curious about their work and how they went about it. I just finished three books written by Albert Einstein - how privileged I feel having learned E=MC squared directly from the mind that first crafted it.
I'm currently finishing up Freud's 'The Interpretation of Dream' while working through Kant's book on 'pure reason.' I would add to this list previous reads of Grant's 'Memoirs' and Mark Twains 'Roughing It' as further examples of first-hand reporting. I hope to do many more of these.
A side note on Opticks. Isaac Newton was Albert Einstein's hero, and Opticks was his favorite among Newton's publications. Late in life while living in the US and teaching at Princton, Einstein asked the British government to send two of England's finest physicists to South America to measure the Sun's light on the moons of Jupiter, and to fund this month-long field research as well. In the midst of also fighting WWII they did, and the scientists brought back first-ever scientific 'proof.' You see . . . at the end of his 1704 Opticks, and following 4 revisions - the final edited just a few days before his death - Newton included a total of 31 'queries,' where he implored future scientists to look into additional discoveries knowing his time had run out. Query #1 states, "Do not bodies act upon light at a distance, and by their action bend their rays ...?" With a wink and a nod to the Father of Physics and to his long-departed mentor, Einstein was able to present to the world final proof, after nearly 250 years, that 'yes,' the forces of gravity can indeed bend the rays of light.
I'm currently finishing up Freud's 'The Interpretation of Dream' while working through Kant's book on 'pure reason.' I would add to this list previous reads of Grant's 'Memoirs' and Mark Twains 'Roughing It' as further examples of first-hand reporting. I hope to do many more of these.
A side note on Opticks. Isaac Newton was Albert Einstein's hero, and Opticks was his favorite among Newton's publications. Late in life while living in the US and teaching at Princton, Einstein asked the British government to send two of England's finest physicists to South America to measure the Sun's light on the moons of Jupiter, and to fund this month-long field research as well. In the midst of also fighting WWII they did, and the scientists brought back first-ever scientific 'proof.' You see . . . at the end of his 1704 Opticks, and following 4 revisions - the final edited just a few days before his death - Newton included a total of 31 'queries,' where he implored future scientists to look into additional discoveries knowing his time had run out. Query #1 states, "Do not bodies act upon light at a distance, and by their action bend their rays ...?" With a wink and a nod to the Father of Physics and to his long-departed mentor, Einstein was able to present to the world final proof, after nearly 250 years, that 'yes,' the forces of gravity can indeed bend the rays of light.
March 8, 2020
Well, naturally this largely went over my head. Listening to it on audio, mostly while I was working, did not make things any easier to follow. It is something you really ought to have in front you, in print. Even then, it's probably hard to keep track with. But nevertheless, there was some interesting material in here. Though I personally am not very scientifically-minded, I have recently been discovering an innate fascination for Isaac Newton within myself.
This book is his treatise on light, colour refraction and the optical mechanics at play in the relationship between the two.
This book is his treatise on light, colour refraction and the optical mechanics at play in the relationship between the two.
May 26, 2017
- start with axioms or things that you believe are universal facts
- use these axioms to come up with propositions
- then with these theorems, conduct experiments to see if your hypotheses can be proven wrong
- The whole theory of light was based on experiments, common sense and geometry. Isn't that beautiful?
I like the structuring of the book, that was more useful than the actual content as it was out of date
- use these axioms to come up with propositions
- then with these theorems, conduct experiments to see if your hypotheses can be proven wrong
- The whole theory of light was based on experiments, common sense and geometry. Isn't that beautiful?
I like the structuring of the book, that was more useful than the actual content as it was out of date
December 7, 2025
I only read the queries. Newton's intuition is at its best here. He foresaw such future physical theories as special relativity (mass-energy conversion), general relativity (gravitational bending of light), atomic theory and also the nature of heat, electricity, and chemical affinity. This shows why Newton was the greatest scientist of all time.
May 5, 2020
Fascinating and amazing
August 29, 2021
Exceptional classic physics text
June 3, 2024
I was very pleasantly surprised on how readable this book was. Very different from the plan of the Principia, this is an account of Newton's experiments with light, concerned chiefly with his investigations of the colors of light. All of us learned in school that Newton discovered that white light was in fact a blend of all the colors of the spectrum, but Newton goes well beyond that in exploring all the ways that spectrum can be dispersed and recombined by prisms, lenses, plates of glass and various kinds of mirrors. What struck me most about Newton's investigations is that he was committed to (and convincingly confirmed) the view that the rays of light had properties that were not changed by reflection, refraction, dispersion and transmission, but that those properties were intrinsic to the rays themselves. The interactions of light rays with matter did not change the properties of the rays, but the properties determined whether and how much the path of the ray would be changed by the interaction. It's a significant departure from previous thinking on the subject and underlies Newton's commitment to the corpuscular conception of light.
March 9, 2016
This groundbreaking treatise on the nature of light was originally written in 1704 by Sir Isaac Newton. This particular book is based on the fourth edition, which was printed in 1730. Using practical and repeatable experiments, Newton demonstrates the nature of light and the origins of color. I'm not sure if this is abridged or not but either way it is quite interesting.
I have read The Principia which is also by Newton, but Opticks is far more understandable and accessible. Principia was mostly based on theory and was translated from Latin, so it is a breath of fresh air to have a book that was originally written in English and has images that are close to the text that refers to them. Also, Opticks is quite practical since the experiments can be reproduced. All you need is a set of prisms, natural light and a way to shut out that light.
The treatise is split into three books, but I don't think it is complete. I believe the preface mentioned that some of the book was removed in the later editions, but I don't think it took away from the book itself. This book also contains a portion containing the history of the treatise and a forward by Albert Einstein.
All in all, this book was quite amazing and well written. I would certainly read this again.
I have read The Principia which is also by Newton, but Opticks is far more understandable and accessible. Principia was mostly based on theory and was translated from Latin, so it is a breath of fresh air to have a book that was originally written in English and has images that are close to the text that refers to them. Also, Opticks is quite practical since the experiments can be reproduced. All you need is a set of prisms, natural light and a way to shut out that light.
The treatise is split into three books, but I don't think it is complete. I believe the preface mentioned that some of the book was removed in the later editions, but I don't think it took away from the book itself. This book also contains a portion containing the history of the treatise and a forward by Albert Einstein.
All in all, this book was quite amazing and well written. I would certainly read this again.
December 26, 2008
Read Cohen's Preface carefully, Einstein's Foreward is negligble.
I enjoyed Newton's precise use of language and his illustrations. Overall, the work was very accessible and must-read material for anyone interested in the history of science or anyone interested in gaining an appreciation of how scientists attempted to explain the natural world using limited means.
I enjoyed Newton's precise use of language and his illustrations. Overall, the work was very accessible and must-read material for anyone interested in the history of science or anyone interested in gaining an appreciation of how scientists attempted to explain the natural world using limited means.
July 21, 2016
Great to read this book, although some of the very mathematical parts were over my head. Especially enjoyed reading the details of the many experiments Newton conducted with prisms and lenses, and reading about his color wheel in his own words. Interesting to see how Newton's contributions to Color Theory are carried forward from this point.
October 22, 2013
When people complain that a book doesn't have pictures, I want to slap them with this and tell them to shut up. Newton was brilliant and you see it on full-display in this work although you will probably need to be a little creative in your Google searches to understand some of the terms he uses.
Currently reading
May 4, 2011Also reading Newton's biography (Gleik), so doing some original research here.
October 9, 2012
Though not a scientist, to read Newton's views and methodologies employed in his experiments was quite an interesting experience...
February 7, 2015
A masterpiece of experimental science.
Displaying 1 - 18 of 18 reviews