*79 
Quantity of Carbon in carbonic Acid. 
Now as the volume of gas was unaltered, it will be fair to 
consider the quantity of oxygene gas consumed as equal to 
the carbonic acid produced, or 29,13 cubic inches. 
Then, if 100 cubic inches of oxygene weigh 33,82 grains, 
29,13 cubic inches will weigh 9,85 grains. 
100 : 33,82 : : 29,13 : 9,85. 
The weight of oxygene consumed was therefore 9,85 grains. 
Charcoal consumed - - 3,98 
Carbonic acid from this statement 13,83 grains. 
Ditto by calculations on carb. acid gas 13,76 
— — 
>°7 
* 3> 8 3 : 3 > 9 8 • •• 100 : s 8 ’ 77 - 
Thus, calculating by the oxygene consumed, 100 grains of car- 
bonic acid gas contain 28,77 charcoal. 
First Experiment on Diamond. 
Thermometer 36° Fahrenheit, barometer 30,20. 
.Our oxygene was made as in the former experiment: it 
contained no carbonic acid ; and on being tried with the im- 
pregnated green sulphate, left a residuum of 3 parts in 100. 
having selected nine of the clearest and most transparent 
Brazil diamonds, we found they weighed 3,95 grains. These 
were ranged in the platina tray, which was placed in the tube, 
and the whole apparatus, adjusted as before, was perfectly air- 
tight. The quantity of oxygene was 49,84 cubic inches, as in 
the last experiment. The same precautions were used to secure 
accuracy in the results as in the former experiment; and it 
would only be an unnecessary intrusion on the time of the 
Society to repeat them. The platina tube was heated red-hot, 
O o 2 
