Phosphorescence 321 



Phosphorus Hermeticus (Baldewein and Mentzel) 



Despite many attempts, particularly by Christian Mentzel (1622- 

 1701) , physician of the Elector, Friedrich Wilhelm of Brandenburg, 

 to prepare phosphors similar to the Bolognian variety, no success 

 was attained until the last quarter of the century. In 1673 Christolph 

 Adolph Baldouin or Baldewein (Balduinus) , a magistrate of the 

 town of Grossenhayn in Saxony and devoted to the fashionable pur- 

 suit of alchemy, prepared the second artificial phosphor, the phos- 

 phorus Balduinus or phosphorus hermeticus."^ It was made from 

 chalk and nitric acid, believed to be the alkahest or universal sol- 

 vent, and was presumably an impure calcium nitrate. The method 

 of preparation was not accurately described and there is a possi- 

 bility that some sulphur was present. Baldouin entitled his paper, 

 " Phosphorus hermeticus sive magnes luminaris." It appeared in 

 the Miscellanea Curiosa'' for 1673-1674 and was also published as 

 an appendix to a pamphlet entitled, Aurum Superius et Inferius 

 Aurae Superioris et Inferioris Hermeticum, Amstelodami, 1675. 

 Baldewein's translators have all complained of his enigmatic lan- 

 guage, known only to those initiated in the mysteries of alchemy. 



A sample of Baldewein's phosphor was sent in a gilded silver box 

 to Henry Oldenburg, Secretary of the Royal Society 



as a small present to his Majesty as founder and patron of your Society; 

 and to the illustrious President, Council and Members thereof. This 

 phosphorus contains the real spark, yea the most secret soul of the fire 

 and light of nature, consequently the invisible fire of philosophers; at- 

 tracting magnetically the visible fire of the sun, and afterwards emitting 

 and diffusing in the dark the splendour of the same.-® 



Oldenburg expressed the thanks of the Society, whose members 

 had witnessed the ability of Baldewein's gift to absorb and shine 

 not only by " Daylight, even when the weather was gloomy and 

 misty, but also by the Flame of a Candle. And 'tis hoped, that the 

 said Presenter will so far extend his generosity ... as to impart to 

 them the way of preparing the same; to be Recorded in their 

 Register books, as a perpetual monument of his ingeniosity and 

 frankness." 



2^ In the articles by R. Lentilius (1685) and O. Jacobaeus (1677-1679) , translated in 

 the Collection academique etranger (vol. 6) of the French Academy (twelve volumes 

 of abstracted translations of foreign publications) the " phosphor herm^tique " is the 

 element phosphorus. 



^^ From a translation of Balduinus' letter in Phil. Trans, abbreviated by Hutton, 

 Shaw and Pearson, 2: 386, 1809. Original in Latin in Phil. Trans. 10: 788-789, 1676, 

 with Oldenburg's statement. In the Phil. Trans. (No. 134: 842) a letter from Malpighi, 

 dated March 9, 1677, told of Zagonius, who prepared the material and made pictures 

 with the Bolognian phosphor, but the secret died with him. 



