This articleScience & Technology at Scientific American.com: Inconstant Constants -- [ COSMOLOGY ] -- Do the inner workings of nature change with time? is a full length free one on the Scientific American website, and is not too bad.
I dip into Scientific American every now and then, but find its articles often have a bit of a readability issue. I think it is because they are often written by the researchers themselves, not journalists or specialist science writers. The articles therefore come across as, well, stodgy, for want of a better word.
New Scientist has a lively, often humorous, style, but seems to perhaps run too many "wacky" ideas by loner scientists. And (from what I can gather) they also seem to have a bit of an accuracy issue in that mag too.
I used to like "Discover" a lot, and bought it regularly for well over a decade. It was never very newsy as such, but had some good writers. I think it changed ownership, the style changed a bit, and besides, with any magazine, I think you eventually tire of them and need a break. Maybe I should try it again.
Back to the Scientific American article, it contains this curious bit of trivia:
"One ratio of particular interest combines the velocity of light, c, the electric charge on a single electron, e, Planck's constant, h, and the so-called vacuum permittivity, 0. This famous quantity, = e2/20hc, called the fine-structure constant, was first introduced in 1916 by Arnold Sommerfeld, a pioneer in applying the theory of quantum mechanics to electromagnetism. It quantifies the relativistic (c) and quantum (h) qualities of electromagnetic (e) interactions involving charged particles in empty space (0). Measured to be equal to 1/137.03599976, or approximately 1/137, has endowed the number 137 with a legendary status among physicists (it usually opens the combination locks on their briefcases)."