I. A paper of the Honourable Robert Boyl's, deposited with the secretaries of the Royal Society, Octob. 14. 1680. and opened since his death; being an account of his making the phosphorus, etc

Abstract

There was taken a considerable quantity of Man's Urine (because the Liquor yields but a small proportion of the desired Quintessence ) and of this a good part at least, had been for a pretty while digested before it was used. Then this Liquor was distilled with a moderate Heat, this the Spirituous and Saline parts were drawn off; after which the Superfluous Moisture also was abstracted (or evaporated away) till the remaining Substance was brought to the consistence of a somewhat thick Syrup , or a thin Extract . This done, it was well incorporated with thrice its Weight of fine White Sand ; and the Mixture being put into a strong Stone- Retort , to which a large Receiver (in good part fill'd with Water) was so joyn'd, that the Nose of the Retort did almost touch the Water: Then the two Vessels being carefully luted together, a naked Fire was gradually administered for Five or Six Hours, that all that was either Phlegmatick or Volatile might come over first.