in the Experiment above recited we observ'd, that Oyl of Vitriol and water being first shaken together, the volatil salt of Sal Armoniac being afterwards put to them, produced a sensible Coldness; yet I found, that if a little Oyl of Vitriol and of the volatile Salt were first put together, though soon after a considerable proportion of water were added, there would be produc'd not a Coldness, but a manifest degree of Heat, which would impell up the liquor in the Thermoscope to the height of some inches. And I remember too, that though Salt of Tartar will, as we shall see e're long, grow hot in the water, yet having distill'd some Salt of Tartar and Cinaber in a strong fire, and put the whole Caput mortuum into distill'd or Rain-water, it made indeed a hissing there as if it had been Quick-lime, but produced no Heat, that I could by feeling perceive. I shall adde, that not onely, as we have seen already, some unheeded Circumstances may promoteor
