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Spectroscope Apparatus. 



SPECTROSCOPE APPARATUS. 



In our first volume, p. 362, we published a paper on " Spectrum 

 Analysis," in which the elementary principles of the process 

 were explained; and in vol. iii. p. 338, will be found a very 

 important article by Mr. William Huggins on " Spectrum 

 Analysis applied to the Stars." In this paper, Mr. Huggins 

 details many interesting results, arrived at through his own 

 admirable investigations, and he prefaces this part of the sub- 

 ject by a very lucid explanation of spectroscope philosophy. 

 Diagrams are also given of the spectra of several of the most 

 important metallic and other substances, and of those afforded 

 by ac Orionis, Sirius, and Aldebaran. Since this account was 

 written, Mr. Huggins has continued his researches with a 

 perseverance and skill that have placed him in the first rank 

 of observers, and enabled him to throw light upon questions 

 of the highest interest in astronomy and physics. We hope 

 very shortly to lay before our readers a full account of these 

 investigations ; and, in the meanwhile, proceed to offer some 

 remarks which may assist those who desire to enter upon 

 spectroscopic inquiries, or to understand what other investi- 

 gators have done. 



We recommend those to whom the question is still new, 

 to consult the two articles to which we have referred, as they 

 will thus obtain the information necessary for the commence- 

 ment of the study. We shall in this place merely remind them 

 that a solar spectrum, or prismatic image of the sun, consists 

 of a ray of sunlight opened like a fan, and spread out so as to 



