4*4 Dr. Hulme's Experiments and Observations 
Exper. g. A piece of uncommonly shining wood was intro- 
duced above water, at 58 minutes past 8 P. M. it remained 
for a short time very luminous, but at 25 minutes past g the 
light was greatly diminished ; at 20 past 10 it was nearly extin- 
guished; and at 2 g past 10 was quite dark. It was then exposed 
to atmospheric air, and the light revived very brightly. 
Exper. 10. The same experiment was repeated, at 35 minutes 
past 8 P. M. the shining property was much diminished at g ; 
and at 10 it was very faint. The next evening, it continued 
merely visible. The wood was now taken out, and the light 
soon revived very strongly. The following night, it was still 
moderately lucid; but on the next evening nearly extinct. 
Exper. 11. Finding, by the above experiments, that the light 
of shining wood was extinguished by this species of gas, and 
restored by atmospheric air, the following three trials were 
made, to discover, in some degree, how long its light might be 
kept in a latent state, and then be revived. At g P. M. several 
fragments of shining wood, tied up in a piece of gauze, were 
introduced above water, into the hydrogen gas, and the light 
was gradually extinguished during that evening. They were 
kept there in that dark state 48 hours, were then taken out, 
and exposed to the open air, when, after a little time, the light 
re-appeared. 
Exper. 12. On the 2d of October, another fragment of ex- 
ceedingly shining wood, two inches and an half long, and pretty 
thick, was put above water in the evening, and its light was 
gradually extinguished. On the second night, it was taken out 
perfectly dark, but its light recovered by degrees, and became 
brilliant. It was introduced again, that evening, into the same 
gas, and its light disappeared. On the third night, it was again 
