John Naylor
Interested in the physics of sights and sounds in nature.
Author of “Out of the Blue, A 24-hour Skywatcher’s Guide”, “Now Hear This, A Book About Sound” & "The Riddle of the Rainbow"
- Died OTD, French physicist, Felix Billet, published in 1868 results of an experiment in which he illuminated a thin, vertical stream of water with sunlight and managed to see 19 rainbow orders including supernumeraries. He named it “la rose des arc-en-ciel”, known in English as Billet’s Rose.
- I went the the Natural History Museum (London) In June 2019 to see Luke Jerram's splendid Museum of the Moon. Although the surface of the sphere was smooth, the shading fooled one's eye into interpreting it as embossed. My tactile acuity with Braille map didn't my match visual acuity!
- Moire patterns are often noticed as one's view of the elements that create them changes. Here is a short film of a moire formed by Venetian blinds and a garden fence with open horizontal slats.
- If ever you need proof that a rainbow is centred on the ye of the beholder…
- Amazing footage #iTeachPhysics #Science 🧪
- I saw the same thing many years ago as I travelled by train across SW London. The foot of the bow appeared to leap from one building to the next. This was long before the days of smart phones, so the only record is a memory!
- This morning frost on a plastic manhole cover reveals the embedded metal grid that strengthens it.
- The first systematic measurements of the speed of sound in water were made in Lake Geneva in November 1826, by Daniel Colladon a Swiss physicist, with the help of his father, some two centuries after the earliest measurements of the speed of sound in air.
- L. Galvani d OTD, became interested in animal electricity when a student dissected a frog’s leg while another operated a static electricity generator, noticed that when it sparked the frog’s leg contracted involuntarily. Is it possible to claim a frog, martyr to science, had picked up a radio wave?
- E.Chladni b OTD 1756, known for the patterns formed on a glass plate sprinkled with fine sand & exited with a bow, was also the first person to measure the speed of sound in gases other than air by comparing the pitch of an organ pipe filled with a gas with that filled with air.
