Vietnam or Thailand ? Vote for the TOP Country of the Week !
Updated: May 27, 2025
Adams's final verdict was: "I fear they are of no value. It is pretty evident that, when he wrote these notes, Newton's mathematics were a little rusty." R. S. Phil. Trans. The experiment had been made before by one who did not understand its meaning;. But Sir George G. Stokes had already given verbally the true explanation of Frauenhofer lines. Abh. d. Kon. Bohm. d.
Frauenhofer, of Munich, took him up in 1805, and soon produced, among others, Struve's Dorpat refractor of 9.9 inches diameter and 13.5 feet focal length, and another, of 12 inches diameter and 18 feet focal length, for Lamont, of Munich. In the nineteenth century gigantic reflectors have been made. Lassel's 2-foot reflector, made by himself, did much good work, and discovered four new satellites.
We, that once bade the world stand aside when the question arose about glasses, or the graduation of instruments, were now literally obliged to stand cap in hand, bowing to Mr. Somebody, successor of Frauenhofer or Frauendevil, in Munich! Who caused that, we should all be glad to know, if not the wicked Treasury, that killed the hen that laid the golden eggs by taxing her until her spine broke?
Sometimes Uranus shows Frauenhofer lines, indicating reflected solar light. But generally these are not seen, and six broad bands of absorption appear. One is the F. of hydrogen; another is the red-star line of Jupiter and Saturn. Neptune is a very difficult object for the spectroscope.
Frauenhofer, at the beginning of the nineteenth century, while applying Dollond's discovery to make large achromatic telescopes, studied the dispersion of light by a prism. Admitting the light of the sun through a narrow slit in a window-shutter, an inverted image of the slit can be thrown, by a lens of suitable focal length, on the wall opposite.
We, that once bade the world stand aside when the question arose about glasses, or the graduation of instruments, were now literally obliged to stand cap in hand, bowing to Mr. Somebody, successor of Frauenhofer or Frauendevil, in Munich! Who caused that, we should all be glad to know, if not the wicked Treasury, that killed the hen that laid the golden eggs by taxing her until her spine broke?
So I am not afraid of that threat; and as to maledictions, you are much too kind and good-natured to utter such stuff; and, besides, curses are just as harmless and useless as blessings. The Frauenhofer lines tell us all the secrets of hell, and so I am not at all afraid of them. But I am terribly afraid, dear father, that the road which you have pursued will lead us to ruin in a very short time."
The number of colours forming images is so numerous as to form a continuous spectrum on the wall with all the colours red, orange, yellow, green, blue, indigo, and violet. But Frauenhofer found with a narrow slit, well focussed by the lens, that some colours were missing in the white light of the sun, and these were shown by dark lines across the spectrum.
Boyle, Cavendish, Priestley, Lavoisier, Black, Dalton and others had laid a broad foundation, and Young, Frauenhofer, Rumford, Davy, Joule, Faraday, Clerk-Maxwell, Helmholtz and others built upon that and gave us the new physics and made possible our age of electricity.
In 1868 Huggins compared the spectrum of Winnecke's comet with that of a Geissler tube containing olefiant gas, and found exact agreement. Nearly all comets have shown the same spectrum. A very few comets have given bright band spectra differing from the normal type. Also a certain kind of continuous spectrum, as well as reflected solar light showing Frauenhofer lines, have been seen.
Word Of The Day
Others Looking