340 



Dr. B. Hasselberg on the 



Wiillner's Acetylene Spectrum. 



Description. 



The spectrum begins 

 with a tolerably bright 

 field at nearly the same 

 place at which the spec- 

 trum of carbonic acid 

 begins. In the middle 

 of this field a bright line 

 is faintly seen, probably 

 H« 



After a feebly illumi- 

 nated field a second 

 bright field begins at ... 

 A dark field 5' broad fol- 

 lows, upon which appears 



a single bright line 



Another bright field be- 

 gins at 



bounded on its more re- 

 frangible side by a bright 



line 



In the dark space follow- 

 ing of 3' breadth a bright 



line ... 



A band begins at 



bounded by a double f 



line at \ 



The next dark field con- 

 tains a bright line at ... 

 A very bright orange field 

 begins with an ill-defined 



bright line at 



which extends with 

 diminishing brightness 

 through a breadth of 13'. 

 This field contains at J 

 two bright lines, and \ 



further a bright line at 



A shaded field begins at 



of 11' breadth, and 

 which shows several 

 lines at 



The last of these lines 

 bounds the fields on its 

 more refrangible side. 

 The spectrum, consisting 

 of beautifully shaded 

 fields showing faint lines, 



continues until at 



there appears the well- 

 known greenish-yellow 



Spectrum of Carbon 

 Oxide. 



6620 6622-0 



6567 



6475 



6330 

 6305 



6235 



6204 

 6192 

 613£ 

 6124 



6097 



6089 



6037 

 6023 



5978 



5950 



5873 

 5838 

 5804 



5609 



6469 



6298-5 



Remarks. 



Commencement 

 of one of the 

 chief bands. 



Spectrum of Hydrogen. 



\. 



Weaker bands. 



Bright band 

 begins. 



6078 



5607-5 



A principal band 

 of CO. 



Very bright 

 band. 



Remarks. 



6562*1 



6328-7 



6235-0 



6198-9 



6134-1 

 6119-7 



6100-1 



6032-4 

 6021-6 



5978-1 



5950-1 

 5939-6 

 5932-5 



5887-4 

 5834-7 

 5811-3 



H«(i). 



Distinct line. 



Bright line. 



Very bright line. 



1 Very bright 

 J lines. 



Limit of group 

 of lines. 



1 Very bright 

 J lines, 

 f Centre of a 

 \ double line. 



I Bright lines. 



} Principal lines 

 of the hydro- 

 gen spectrum 



