A flowing electrochemically excited liquid-nitrogen-cooled He-air-CH
4-(CO) laser was operated in

-switched fashion yielding 20 CO laser lines below 5.0 μ. These laser lines were measured to occur from 4.7848 to 4.9880 μ. The lines were all identified to result from

CO vibrational-rotational transitions as low as

. Nine such

transitions were measured.