At firſt ſight I may ſeem to have acted erroneouſly, by ſeparating this from the other gems, and inſerting it here; but after due conſideration, I know not where to place it better. It has never yet been decompoſed by the liquid analyſis^[52]; and when expoſed to the fire in an open veſſel, it is wholly conſumed, burning with a lambent flame. This deflagration, though ſlow, ſhews decidedly its affinity to the inflammables: beſides, in the focus of a burning glaſs, it leaves traces of ſoot^[53]. When further experiments teach us better, I ſhall willingly correct my error.