98 



(liroiigli a length unit makes about 9 times as many collisions as 

 would be exj)ected from tUe kinetic theory, while in neon the 

 number of collisions is nearly normal. This shows clearly, why 

 tn argon non-elastic impacts above the excitation potential have a 

 marked effect, while under similar conditions in neon they are 

 hardly noticeable. 



Eindhoven, Laboratory of the 

 Philips Incandescent Lamp Works. 



