and on the Nature of t lie Diamond. 321 



Second Experiment on Animal Charcoal. 



Thermometer 59° Fahrenheit, barometer 29'43. 

 Some of the animal charcoal of last experiment was heated 

 to redness under sand for one hour. 4 grains were placed 

 in the platina tray ; and as we were so much embarrassed 

 in the last experiment with the saline matter which adhered 

 to the trav, we exactly balanced it wiih its contents. Our 

 oxvgen, made as usual, left a residuum of 2 parts in 100, 

 and we began with 49-84 cubic inches. When every thing 

 was adjusied, and the platina tube red-hot, on passing the 

 oxygen, flashes resembling lightning ran along the glass 

 tube ; and this was repeated 5 or v times. The whole of 

 theaas became very cloudy, exhibiting a turbid milky ap- 

 pearance. The tube was rendered white-hot by the com- 

 bustion of the carbonaceous matter in oxygen. The fire 

 was kept up about 8 minutes, and the gas passed several 

 times. When all was cool, we could observe no alteration 

 in the volume of gas by the register. The tray contained a 

 mixture of salts j and, being weighed, was lighter by 3-2 

 grains. This loss was not wholly carbon, for it is well 

 known that animal substance contains a variety of salts, as 

 phosphates, muriates, &c., some of which, though not 

 volatile in a low red heat, might be decomposed and dissi- 

 pated in the intense white heat produced by the combustion 

 of the carbonaceous matter m oxygen ; and we accordingly 

 found the internal parts of the gasometers and tubes very 

 slightly covered with a sort of efflorescence. On examining 

 the gas after the experiment, 



Lime water absorbed 41 parts from 100 



The tests for oxygen 55 



Residuum - 4 or an increase of 2. 



100 



Correction for temperature. 

 60° 49-84 



59 -10 add for temp. 



1 diff. or 0-103 49 94 



Vol. 29. No. 1 IG. Jan. IfaOS. X Currijction 



