A bit of trivia. The carbon that they are using is soot made by incomplete combustion.
When I worked for Ray O Vac in the seventies, we used a product called Shawinigan Black. It was made by burning acetylene . One of my colleagues brought a bag of it back to our lab for chemical analysis. When he was going though customs, the agent insisted on opening the bag against the advice of my colleague. A pound of the stuff could fill a very large room and it did.
When I worked for Ray O Vac in the seventies, we used a product called Shawinigan Black. It was made by burning acetylene . One of my colleagues brought a bag of it back to our lab for chemical analysis. When he was going though customs, the agent insisted on opening the bag against the advice of my colleague. A pound of the stuff could fill a very large room and it did.