1826.] jDr. Colqulioun on anevj l^orm of Carbon, 5 



residue resulting from this deflagration had a blackish colour, 

 and contained diffused through it many particles of the filamen- 

 tous carbon still entire and unconsumed. When the soluble 

 part of this product was dissolved out with water, it appeared 

 that the portion which had escaped oxygenation, probably 

 owing to the rapidity with which the action of the chlorate of 

 potash was begun and completed, amounted to little less than 

 one-half of the whole original quantity of filamentous matter. 



When a few of these filaments were similarly exposed to the 

 action of nitre, a deflagration also took place ; but in this 

 instance the action of the salt was much more durable and pro- 

 longed, and the oxygenation of the whole filaments was com- 

 plete. In this case, the saline residue proved to be of a pure 

 white colour, and, on the addition of a little water, was to the 

 last particle dissolved. 



When muriatic or nitric acid was poured upon the aqueous 

 solutions of these saline residues, a strong effervescence took 

 place, and much carbonic acid was disengaged, accompanied 

 with nitrous vapours. 



To ascertain whether any hydrogen could be detected in this 

 carbon, a small tuft of very delicate filaments, weighing 0*30 gr. 

 was put into an agate mortar along with six grains of the black 

 oxide of copper, and the whole thoroughly intermingled by 

 trituration. The mixture was transferred into a tube of green 

 glass closed at one extremity, and freed from hygrometric mois- 

 ture by cautious exposure for a sufficient length of time to a 

 temperature of about 240°. It was then, after having been 

 allowed to cool, brought to a very strong red heat over a spirit- 

 lamp. The result was the deoxidation of the oxide of copper, 

 and the abundant disengagement of carbonic acid gas ; but, 

 during the whole progress of the experiment, there was not the 

 deposition of the smallest trace of moisture. On decomposing, 

 by a similar process, a small quantity of ordinary cherry coal, 

 weighing 0'05 gr. a very distinct deposition of water was formed. 



The conclusion from all these experiments seemed to be of 

 necessity, the highly interesting demonstration, that in the com- 

 position of this carbonaceous substance, there is not present 

 a trace of hydrogen : there was also the stronoiest indication, 

 although in a manner not so decisive, that no foreign ingredient 

 of a more fixed nature, whether earthy or metallic, made any 

 part of it. In order to ascertain, however, a point of such 

 importance, and to determine whether these long needles or 

 filaments were really composed of pure carbon, I subjected them 

 anew to the following experiments. Some of the filaments, 

 weighing 0*62 grain, and which had been previously cut across 

 into small pieces, were deflagrated in a platinum crucible along 

 with 12-4 grains of nitre. The oxidation of the whole carbona- 

 ceous matter was in this experiment complete; for there was 



