39 
CHAP THR, PV. 
PHOSPHORESCENCE OF GASES, AND ELECTRIC 
PHOSPHORESCENCE. 
THE phosphorescence of gases is quite a new dis- 
covery, dating from the year 1859. It is extremely 
probable that many gases are phosphorescent after 
insolation, when large quantities of them are sub- 
mitted to the action of the sun’s rays. We shall 
see in the following chapter that the air probably 
is so, and also that meteoric stones leave phospho- 
rescent streaks in the atmosphere. 
We have already noticed, that substances which 
are not phosphorescent after insolation may be- 
come so after they have undergone the influence 
of an electric discharge. In February, 1859, M. 
Edmond Becquerel communicated to the Academy 
of Sciences at Paris a discovery made by M. Ruhm- 
korff on rarefied air, and worked out afterwards 
by the former. 
M. Ruhmkorff remarked that certain rarefied 
gases, shut up in glass tubes, remained phospho- 
rescent for some seconds after an electric dis- 
