OBSERVATIONS ON SPONTANEOUS LIGHT. %Q 



Exp. 9. A piece of uncommonly mining wood was intro- Repetition of 



duced above water, at 58 minutes paft 8 P. M. it remained extin ^»o n an4 



' .01 refufcitation. 



for a fliort time very luminous, but at 25 minutes pall 9 the (Wood) 



light was greatly diminished ; at do paft 10 it was nearly extin- 

 guiflied ; and at 29 paft JO- was quite dark. It was then 

 expofed to atmofpheric atr, and the light revived very 

 brightly. 



Exp. 10. The fame experiment was repeated, at 35 minutes 

 paft 8 P. M. the mining property was much diminiflied at 9 ; 

 and at 10 it was very faint. The next evening, it continued 

 merely vifible. The wood was now taken out, and the light 

 foon revived very ftrongly. The following night, it was ftill 

 moderately lucid ; but on the next evening nearly extinct. 



Exp. 1 1. Finding, by the above experiments, that the light 

 of fhining wood was extinguiflied by this fpecies of gas, and 

 rcftored by atmofpheric air, the following three trials were 

 made, to difcover, in fome degree, how long its light might 

 be kept in a latent ftate, and then be revived. At 9 P. M. 

 feveral fragments of fhining wood, tied up in a piece of gauze, 

 were introduced above water, into the hidrogen gas, and the 

 light was gradually extinguiflied during that evening. They 

 were kept there in that dark ftate 48 hours, were then taken Extraction for 

 out, and expofed to the open air, when, after a little time, *• nours# 

 the light re-appeared. 



Exp. 12. On the 2d of October, another fragment of ex- Three repetitions 

 ceedingly lhining wood, two inches and a half long, and pretty ?L rf fmitton 

 thick, was put above water in the evening, and its light was 

 gradually extinguiflied. On the fecond night, it was taken out 

 perfectly dark, but its light recovered by degrees, and became 

 brilliant. It was introduced again, that evening, into the fame 

 gas, and its light difappeared. On the third night, it was again 

 expofed to the open air, and the light revived as before. It was 

 then reinftated and extinguiflied, and continued in a dark ftate, 

 from the third to the fifth night, when, being again taken out, 

 it foon Ihone in a pretty vivid manner. It was again intro- 

 duced and extinguiflied as ufual ; and no obfervation was made 

 of it, from fome accidental circumftance or other, until the 10th 

 of November in the evening, when it was taken out, and ex- 

 pofed to the open air for a length of time, but the light did not 

 revive. 



Exp. 



