on the Light emitted from various Bodies. 41 3 
It was retained therein three days and three nights, without 
emitting any light. It was then taken out, and exposed to the 
action of atmospherical air. On the following night it was found 
to be luminous ; but was dark again on the next night. 
Exper. 2. Another piece of fresh herring was put above 
water, at 6 P. M. This was also kept in the gas the same 
length of time, without producing any light. It was then ex- 
posed to the open air, and inspected two successive nights, 
but it remained dark. 
Exper. 3. The same experiment was then made with a piece 
of mackerel, which was taken out on the fourth night, without 
producing any shining appearance. The next evening, it 
emitted a very faint light, which did not continue twenty-four 
hours. 
Exper. 4. A cork, brilliantly illuminated with mackerel-light, 
was introduced above water ; and the light was extinguished in 
about the space of an hour. 
Exper. 5. At 39 minutes past 9 P. M. another luminous cork 
was put above water ; it lost some of its light pretty soon, but 
was not extinct at twelve. 
Exper . 6 . A cork, with herring-light, was introduced above 
water, at 23 minutes past 6 P. M. The light gradually dimi- 
nished, and was only faintly visible at eleven. 
Exper. 7. A fragment of very shining wood was put above 
water, at 9 P, M. and was dark at eleven. 
Exper. 8. Another fragment was put above water, at 40 mi- 
nutes past 8 P. M. at 30 the light was much diminished, and at 
8 minutes past 9 the shining ceased. The wood was then taken 
out, and exposed to the open air, when the light revived in a very 
beautiful manner. 
