on the Light emitted from various Bodies . 
§ »• 
The Effects of oxygen Gas or vital Air * on spontaneous Light . 
EXPERIMENTS. 
Exper. 1. A piece of fresh herring, of about three drams 
weight, was introduced above water, into eight ounces of oxy- 
gen gas. On the second night it was observed to be faintly 
luminous; on the third, the quantity of light was increased; 
on the fourth, it continued nearly in the same state; and oie 
the fifth the light was diminished. 
Exper. 2. A piece of very fresh mackerel,- of the same mag- 
nitude, was also put above water. On the subsequent even- 
ing it was pretty lucid, and continued the same on the night 
following. 
Exper. 3. At 9 P. M. a cork, finely illuminated with' mackerel- 
light,, was introduced above water: it continued very lucid at 
eleven. On the next evening it was dark. 
Exper. 4. Another cork, rendered luminous with the same 
kind of light, was put above water at 1 o P. M. The next morn- 
ing, at six o’clock, only a glimmer of light was perceived, and 
at io'P. M. it was extinct. 
Exper. 5. At 9 P. M. a fragment of shining wood was in- 
troduced above water : it was observed to be still very lumi- 
nous at eleven ; but the light was not quite so vivid, nor so 
extended in breadth, as when the wood was put in. On the 
succeeding night, at eight o’clock,, it remained faintly lucid. 
Exper. 6 . A little after 8 P. M. another fragment of wood, 
* The oxygen gas made use of was obtained from manganese, by means of heat. 
