Oxv PHOSPHORUS.* 



A. CERTAIN German gentleman, who faid he was a Dodor of 

 Phyfic, and newly come from England, paying me a vifit, with 

 the compliments of feveral of my friends in London, after fitting 

 with me sometime, produced a fmall veflel filled with water, at the 

 bottom of which lay fomc fmall pieces of a whitifli fubftance, in- 

 clining to a tinge of yellow ; thefe he took out of the water, and 

 with one of them he traced upon paper fome letters about the fize 

 of a joint of one's finger ; and though at firtl, nothing of thefe let- 

 ters was to be feen on the paper, yet upon removing it into a dark 

 place, the paper feemed to be on fire in every place where the let- 

 ters had been traced : but this fire was very pale or faint, and fe- 

 veral hours afterwards viewing the paper in the dark, the letters 

 -had Hill a lucid appearance. He alfo took a fmall piece of this 

 fubllance and put it between two pieces of whited brown paper^ 

 and rubbing them brilkly fix or eight times with his cane, in the 

 place where the before mentioned fubfi:ance lay, to my great fur- 

 prize, I faw the paper, by means of the fri6lion, burfi: into a flame. 



This medical gentleman told me, that this fubftance was pre- 

 pared by difiillation from urine which had been long kept, and that 

 it could not be preferved, unlefs kept under water : he gave me a 

 piece of it, and with a particle thereof, about the fize of a pin's 

 head, I repeated the before-mentioned experiments three feveral' 



* Mr. Lceuwenhoek calls this fubftanre ligt der nature, which the Latin Trandalor 

 Tenders licmen naturale, in Englifli, natural light : from the dcfcription here g'lTCn, it can. be 

 no other than the Thofphorus of the fliops. 



