66 Kansas Academy of Science. 



spectroscope not only showed the constitution of earthly bodies, 

 but could analyze the sun and stars. 



No limit has been found in the number of solar lines, nor are 

 they confined to the visible spectrum. Photography comes to our 

 aid in studying the invisible spectrum, especially of the violet end. 

 Wonderful improvements have also been made in the manner of 

 obtaining the spectrum. In place of the grating of fine wires de- 

 vised by Fraunhofer rulings are made on speculum metal with as 

 many as 20,000 lines to the inch, by which the spectrum is spread 

 out to twelve feet or more. These photographic charts far surpass 

 the best results of KirchhofiP and Angstrom. In the chemical lab- 

 oratory, however, the refraction spectroscope must remain the com- 

 mon instrument, and the method of curves herewith presented will 

 be found a useful adjunct to its use. 



