on the Light emitted from various Bodies, 4,17 
and supported by a tea-saucer that held about three ounces of 
water. On the second night it was dark, and continued the 
same on the third. It was then exposed to the influence of 
atmospherical air, and, on the next evening, it was pretty 
luminous, and likewise on the succeeding night. 
Exper. 4. At 9 P. M. a cork, smeared with the luminous 
matter of a mackerel, was put into a five-ounce wide-mouthed 
phial, filled with carbonic acid gas, and then closed with a glass 
stopple. It continued to shine pretty vividly for some little 
time; then the light gradually diminished, so that at twelve, 
only a small spark remained. 
Exper. 5. At 10 P. M. another cork, illuminated with mackerel- 
light, was introduced above water, into 24 ounces of the gas ; 
and its light was nearly extinct at twelve. 
Exper. 6. At 8 P. M. a fragment of shining wood was put 
above water, into 24 ounces of the gas : and it had not been 
long there before the light disappeared. It was then taken out, 
and exposed to the action of atmospheric air, when its shining 
property soon returned. 
Exper. 7. Another fragment of brightly shining wood was 
introduced above water, into the same quantity of the gas, at 10 
P. M. and the light was extinguished in the space of an hour. 
After this, it was exposed to the open air, and the light gra- 
dually revived. 
Exper. 8. At 8 P. M. a luminous dead glow-worm was put 
above water into the gas; its glowing appearance gradually 
faded, and in a short time became quite invisible. It was then 
taken out, and the light, by degrees, re-appeared as vivid as 
before. 
3 H 
MDCCCI. 
