Combine one part Fiery Dragon, some Doves of Diana, and at least seven Eagles of mercury, and what do you get? A key precursor to the Philosopher’s stone, according to a rediscovered manuscript handwritten by legendary physicist Isaac Newton. Held in a private collection for decades, the 17th-century document is now in the hands of the Chemical Heritage Foundation, a nonprofit based in Philadelphia, Pennsylvania. The group bought the manuscript in February and is currently working on uploading digital images and transcriptions to an online database so more people can study Newton’s take on the alchemical text.