OBSERVATIONS ON SPONTANEOUS LIGtff. £>J 



Exp. 12. Another cork was introduced above water, with 

 herring-light, at 40 minutes pad 7 P. M. and it remained pretty 

 luminous at eleven. On the following night, it was nearly 

 extinct. 



III. The lafi mentioned azotic Gas, after being tvajhed with 

 Lime Water. 



Exp. 13. A piece of herring, of about three drams weight, 

 was put above water, into this azotic gas, at 5 P. M. On the 

 fecond night, it was dark; on the third, very lucid j and on 

 the fourth, the fame. 



Exp. 1 4. The experiment was repeated, on a piece of her- 

 ring, at 3 P. M. On the fecond evening, it was dark j on 

 the third, pretty luminous ; on the fourth, it was lefs fo j and 

 on the fifth, only a faint light remained. 



Exp. 15. A portion of freih mackerel was then put above 

 water, at 1 1 A. M. On the fecond night, it was obferved to 

 be moderately mining ; on the third, the light was extinct. 



Exp. 16. Another piece of frefh mackerel was introduced 

 above water, at 3 P. M. On the fecond evening, it was flightly 

 luminous ; on the third, it w as dark, and continued fo during 

 the four fucceeding nights. 



Exp. 17. A cork, finely illuminated with herring-light, was 

 next introduced above water, into this gas, at 20 minutes pafl 

 8 P. M. The light was much diminifhed at 45 minutes pafr. 

 8 ; at 1 1 the cork had become almofl dark. On the following 

 night, a glimmer was ftill apparent. 



Exp. 18. Another cork, made very luminous with herring- 

 light, was put above water, at 40 minutes paft 7 P.M. and it 

 continued pretty lucid at eleven. On the next evening, the 

 light was merely vifible. 



A fimilar experiment was made, at the fame time, in atmo* 

 fpheric air, and with nearly the fame effect. 



OBSERVATION. 

 It is a remarkable circumftance, that azotic gas, which is 

 incapable of fupporting light from combuftion, mould be fo 

 favourable to the fpontaneous light which is emitted fromvfiijjes, 

 as to preferve its exiftence and brilliancy for fome tim&? iuhen 

 applied upon a cork; yet that it fhould prevent thefe/h of the 

 herring and the mackerel from becoming luminous, and alfo 

 extinguifh the light proceeding from rotten wood, 



