(1692) zag , ik zag .a pea , which he states to be a mineral and which he calls the light of nature ; this had been communicated to a certain Chemist in that city where he then was ; he added that it had also been presented to that Gentleman from whom he had received it , and that I had one half of that presented substance , and that he had seen that when that Gentleman took the substance out of the water , and put it in his hand , it exhaled on all sides a fume , vapour , or smoke , and when he held the hand a little under a table - cover in the dark , that substance lit up and burned like some rotten wood , etc .No sooner had I received this substance but I judged that it was the same kind of substance which I said heretofore I had received from the High German Gentleman .