BASQUIN. — THE ARC SPECTRUM OF HYDROGEN. 



167 



Wave 



lengths. 



4279.77 

 4280.72 

 4281.25 

 4281.85 

 4282.48 

 4283.38 

 4284.15 

 4285.26 

 4287.58 

 4290.25 

 4293.45 

 4294.86 

 4296.98 

 4298.55 

 4300.92 

 4302.63 

 4305.24 

 4307.07 

 4309.98 

 4311.89 

 4315.12 

 4317.07 

 4820.68 

 4322.74 

 4324.59 

 4320.61 

 4328.77 

 4331.38 



The aluminium arc in hydrogen gives a beautiful fluting with first head 

 at 4241.26 and running toward longer wave lengths. This fluting ap- 

 pears equally well in an atmosphere of ammonia. The following table 

 gives the wave lengths and intensities of the principal lines : — 



