First printings of three important papers demonstrating the universal validity of Newton's laws of gravity and motion. Extracted from Philosophical Transactions 93, pt2; 94, pt. 2; 114, pt. 3.
Isaac Newton developed the laws of physics (motion and gravity) from observations on earth and the motions of the moon and planets within the solar system, and though scientists believed these laws to be universal, it was more than 100 years before they were demonstrated to hold outside the solar system. William Herschel published the results of a 25 year program of measuring the motion of binary stars in in two parts, in 1803 and 1804. He was able to demonstrate that orbital motion of these double stars obeyed Newton’s law of gravity and motion, thus providing the first scientific evidence of the validity of the laws of physics outside our solar system. More than 20 years later in 1824, William Herschel’s son John Frederick William Herschel (1792–1871) published an even larger study of the motion of double stars (360 in all) that supported his father’s earlier work.
“Account of the Changes that have Happened, During the Last Twenty-five Years, in the Relative Situation of Double-Stars, with an Investigation of the Cause to which they are Owing” by William Herschel (Philosophical Transactions of the Royal Society of London 93 Part 2 pp. 339-382, 1803)
“Continuation of an Account of the Changes That Have Happened in the Relative Situation of Double Stars” by William Herschel (Extract from Philosophical Transactions of the Royal Society of London 94 Part II pp. 353-384, 1804)
“Observations of the Apparent Distances and Positions of 380 Double and Triple Stars, Made in the Years 1821, 1822, and 1823, and Compared with Those of Other Astronomers; Together with an Account of Such Changes as Appear to Have Taken Place in Them Since Their First Discovery. Also a Description of a Five-Feet Equatorial Instrument Employed in the Observations” by John Herschel (Philosophical Transactions of the Royal Society of London 114 Part 3, 1824)
Very good condition. The first and third extracts are untrimmed and bound in early paper wraps; the second is a more recent extract and lacks wrappers. All are housed in an attractive custom clamshell box.