A funny and informative pop-sci collection of Isaac Asimov's articles on the history of science up to the mid-1960s, in our period of modern physics. Asimov defines the divide in the chapter "A Piece of The Action": In the Classical Physics period from ancient times until 1900, before Max Planck introduced Planck's constant, energy was considered continuous (h=0). In the Modern Physics period, energy is considered to be composed of quanta (h>0). Planck invented quanta merely to account for black-body radiation, which Gustav Robert Kirchhoff and Robert Wilhelm Bunsen had been struggling to interpret since developing spectroscopy in 1859, but it turned out quanta also justify the photoelectric effect, the study of which earned Albert Einstein a Nobel Prize in 1921 (a common misconception is Einstein was awarded a Nobel for the theory of relativity, but it was for the photoelectric effect).
There are a couple of articles about the evolution of modern physics from deterministic to statistical, thanks to Werner Karl Heisenberg and the introduction of the uncertainty principle, which earned him a Nobel Prize in 1932. There are a few articles about the work of Sir James Chadwick, Niels Bohr, and Hideki Yukawa, but I'm not really interested in subatomic particles.
I'm not that interested in space either and there's a lot in the book (atmospheres, Law of Universal Gravitation, star clouds, on the plausibility of "hyperspace" or "inertialess drive", etc.). There's also an article in there about cetaceans and sound traveling underwater if you're into that kind of thing.
I was really excited by Asimov's writing on entropy, "Order! Order!" and "The Modern Demonology." In "Order! Order!" Asimov explains theories on the infinitely expanding universe versus the finite universe doomed to end in heat death (entropy maximum). In "The Modern Demonology" he explains the thought experiment Maxwell's demon and describes natural selection as another analogy on the illusion of entropy-decrease (called Darwin's demon) that is not accounting for the whole system. Since he wrote in the 1960s, it was long before He Jiankui from my alma mater, Rice University, used CRISPR/Cas9 to genetically modify human babies in 2018 and created a new illusion of entropy-decrease. Of course there is no such thing as a decrease in entropy (maybe with quasars or black holes which are too unknown). Asimov warns, "All knowledge of every variety is in the mind of God—and the human intellect, even the best, in trying to pluck it forth can but 'see through a glass, darkly.'"
Some of the articles appear in his other collection, Adding a Dimension, which I liked better overall than this collection because it included some of his articles on mathematics. The article which also appear in Adding a Dimension are "The Rigid Vacuum" (on James Clerk Maxwell's equations and Heinrich Rudolf Hertz's work on using radio waves for communication in 1888), "The Light That Failed" (on Albert Abraham Michelson's failed experiment in 1882 which finally killed the theory of ether), and "The Light Fantastic" (which predicted in the 1960s that lasers would be the basis of our telecommunications system—they are). I recommend these articles in either of Asimov's collections but I am biased on these three articles because I have two degrees in electrical engineering.