In general, substances that burned in air were said to be rich in phlogiston; the fact that combustion soon ceased in an enclosed space was taken as clear-cut evidence that air had the capacity to absorb only a finite amount of phlogiston.
Generalno, za supstance koje sagorevaju u vazduhu se kaže da su bogate flogistonom; činjenica da sagorevanje ubrzo prestaje u zatvorenom prostoru je uzimana kao jasan dokaz da vazduh ima kapacitet da apsorbuje samo konačnu količinu flogistona.