ON TIIF. QUANTITY OF CARBON IN CARBOLIC ACID. 0.0% 



ia weight 7*3 grains. This experiment was repeated with 

 exactly the same result. The thermometer and barometer 

 remaining the same, we take the volume as before cor* 

 rected. 



21*58 cubic inches. 

 21*58 :7*3 :: 100:33*83 



Then 100 cubic inches of oxigen gas at mean temperature lOOcub.inche* 

 and pressure weigh 33*82 grains. After these experiments, wei £h^-82 

 we examined Davy's researches on nitrous oxide, and had 

 the satisfaction to find, that his estimate, both of carbonic 

 acid and oxi gen gasses, agreed almost exactly with ours, 



The next point was to ascertain whether limewater would Whole of car- 

 take the whole of the carbonic acid gas from a mixture with ^"^bedV 38 

 oxigen, or common air; we therefore mixed a known quan- common air by 

 tity of carbonic acid gas with a certain quantity of common Ume wateF 

 air, and on trying it with our eudiometer and limewater, the 

 whole of the carbonic acid gas was in a short time absorbed, 

 We also found, that, though the solution of green sulphate 

 saturated with nitrous gas would not take up the whole of 

 the carbonic acid gas, yet the simple green sulphate, merely or <*reen rat 

 by its water of solution, absorbed it very readilv. phateof iron, 



Jt may be proper to notice here, that though we repeatedly Gas from hyp, 

 tried the oxigen procured from hyperoxigenised muriate °f ™ntained°no* 

 potash by the eudiometer and limewater, it never gave the trace of carbo- 

 least trace of carbonic acid. nic acid * 



Experiment with Charcoal from Box-wood, 



The thermometer being at 42° Fahrenheit, barometer at Experiment 



30*2, vve kept some box-wood charcoal red hot for a consi- withbox wo °4 

 ■ill- i i i'ii • charcoaj. 



derable time under sand, and weighed 4 grains as expedi- 

 tiously as possible; this, being put into the platina tray, was 

 pushed to the middle of the platina tube; the oxigen (made 

 from hyperoxigenised muriate of potash over mercury) was 

 contained in gasometer No. 1 ; No. 2 was empty, Every- 

 thing being adjusted and found perfectly air-tight, the com- 

 munication with the small receiver R was closed, and the 

 common air contained in the tubes and sockets, amounting 

 only to 2*84 cubic inches, was driven out by a pressure of 

 oxigen from gasometer No. I. When several cubic inches 



had 



