let them be separable by the Fire? And on this Occasion, Eleutherius, give me leave to mention to you two or three sleight Experiments, which will, I hope, be found more pertinent to our present Discourse, than at first perhaps they will appear. The first is, that, having (for Tryals sake) put a quantity of that Fugitive Concrete, Camphire, into a Glass Vessel, and plac’d it in a gentle Heat, I found it (not leaving behinde, according to my Estimate, not so much as one Grain) to sublime to the Top of the Vessel into Flowers: which in Whiteness, Smell, &c. seem’d not to differ from the Camphire it self. Another Experiment is that of Helmont, who in several places affirms, That a Coal kept in a Glass exactly clos’d will never be calcin’d to Ashes, though kept never so long in a strong Fire. To countenance which I shall tell you this Tryal of my own, That having sometimes distill’d some Woods, as particularly Box, whilst our Caput mortuum remain’d in the Retort, it continued black like Charcoal, though the Retort were Earthen, and kept red-hot in a vehement Fire; but as soon as ever it was brought out of the candent