Spectral analysis / by F. Hoppe-Seyler.

  • Hoppe-Seyler, Felix, 1825-1895.
Date:
1872
Catalogue details

Licence: Public Domain Mark

Credit: Spectral analysis / by F. Hoppe-Seyler. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    sources of light such as the light of the sun, lamp-light, phos- phorescent bodies, as well as the flame of many other pro- cesses of combustion to a very minute examination. Already in the year 1802 WoUaston observed, that the solar spectrum exhibited some black lines, which he considered to be the boundaries of the different coloured rays of light. In 1814 the renowned optician Frauenhofer of Munich, first described more minutely the solar spectrum, adding to his description numerous measurements and an excellent sketch of the solar spectrum engraved by himself; he specified the principal dark lines by letters of the Alphabet, an arrangement, which has since that time become generally adopted, and he very inge- niously made use of these fines to measure the strength of the refractive light of the Prisms and thereby laid the real foundation of spectral analysis. The dark fines in tfie solar spectrum are still called Frauenhojers lines, after their dis- coverer. The whole of the communication sent by Frauen- hofer to the Academy in Munich, which is not more than 33 pages in length, and in which he describes this discovery, remains to this day an exceedingly copious source of know- ledge particulary as regards spectral phenomena. The later examinations of the fight of different sidereal and telluric sources have until now added very little, that is new to for- mer discoveries. The renowned Sir David Brewster, whose loss we have recently been called to deplore, extended the nformatio n respecting the Solar Spectrum and particidarly taught us to understand the influence of coloured substances on the different coloured parts of the Spectrum. The English Natural Philosopher Stokes, and about the same time Ang- strom in Sweden attained very important results with respect to the relation of the light absorbed by a body, to the rays