The sunbeam and the spectrascope / by Howard Townsend.

  • Townsend, Howard, 1823-1867.
Date:
1863
Catalogue details

Licence: Public Domain Mark

Credit: The sunbeam and the spectrascope / by Howard Townsend. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    or photosphere, a better term—the solar spectrum would give a series of brilliantly colored bright bands. It has been stated that vapors are opaque to their own class of rays ; therefore, since the rays produced by burning iron or mag- nesia or lithium or other metals, are NOT transmitted through the vapors produced by the combustion of those metals, the solar spectrum gives an extensive series of dark bands. That every black line in the solar spectrum repre- sents rays emitted from some metallic body in the state of combustion in the sun, is exceedingly doubtful. It has been already shown that many of the dark lines are due to the want of absolute transparency of our own atmosphere. But, Kirchoff's view of the coincidence of the black lines of the solar spectrum with the bright lines of terrestrial flames is a fair deduction from his experimental observations. Whilst these inquiries of Kirchoff, Bunsen and others have been progressing, investigations elsewhere have brought corroborative evidence. The party of Astrono- mers who went to Spain in 1860, to note with all accuracy the phenomena of the solar eclipse of that year, brought back evidence of tongues of flame or clouds glowing with the reflected lights of an intense combustion coming strong- ly into view when the bright light of the sun was obscured by the moon's body. Prof. Airy, states it as his belief that the sun is boiling up and that the prominences observed werejumes given off. The sun's disc is covered by masses of curiously shaped and ever moving forms, called by their discoverer, Mr. Hasting, the willow leaves. The inference is that these are tongues of flame ever bursting from this incomprehen- sible mass and dispersing light and its attendant forces to all the planets. By the aid of optical science, of chemical experiments, and astronomical observations, we are advanced to the fol- lowing deductions :