4to Dr. Hulme's Experiments and Observations 
Exper. 4. At 40 minutes past 7 P. M. another cork, rendered 
very luminous with herring-light, was introduced above water. 
This cork, at 1 1 P. M. was not found so lucid as that in the 
third experiment. On the next evening, a glimmer of light was 
still perceptible. 
Exper. 5. A fragment of very shining wood was introduced 
above water, into this gas ; and it was rendered dark in about 
15 minutes. 
Exper. 6. The experiment was repeated ; and the light was 
again extinguished in about 15 minutes. In another experiment, 
it was extinguished in about 2.5 minutes. 
II. Atmospheric Air rendered azotic , by burning Spirit of Wine 
in it , when confined above Water. 
Exper. 7. A portion of fresh herring, of about three drams, 
was put above water, into this azotic gas, at 5 P. M. On the 
second evening, a spark of light was observable ; on the third, 
the quantity of light was increased ; on the fourth, it was again 
diminished. 
Exper. 8. At 3 P. M. the usual quantity of herring was in- 
troduced above water. On the second night, it remained dark ; 
on the third, it was moderately luminous ; on the fourth, it was 
less so ; on the fifth, the light was extinct. 
Exper. 9. A piece of fresh mackerel was next put above 
water, at 1 1 A. M. On the second evening, it was found to be 
slightly luminous ; it remained so on the third ; on the fourth, 
it was dark. 
Exper. 10. Another piece of fresh mackerel was introduced 
above water, at 3 P. M. On the second night, it was found 
to be slightly luminous ; but on the third, it was dark ; and no 
