162 History of Luminescence 



The second (1738) edition contains an excellent article on phos- 

 phorus, using this word to designate any type of body emitting light 

 at a low temperature, rather than for the element phosphorus spe- 

 cifically. The word " phosphorescence " is a more modern term not 

 found in Chambers. 



The two-page article on " Phosphorus " divided them into the 

 natural and artificial variety. (1) Natural phosphori luminesce 

 without any preparation such as glowworms, lantern-flies, rotten 

 wood, the eyes, the blood, scales of fish, flesh, sweat, feathers of 

 certain animals; diamonds when rubbed, sugar and sulphur when 

 pounded; " sea water and some mineral waters, when briskly agi- 

 tated," cat's fur or horse's backs when rubbed. Dr. Croon tells us 

 that 



upon rubbing his own body briskly with a well-warmed shirt, he has 

 frequently made both to shine; ... all natural phosphori have this in 

 common, that they do not shine always; and that they never give any 

 heat. But that, which, of all natural phosphori, has occasioned the most 

 speculation, is the Baro7netrical or mercurial phosphorus. 



A considerable account is given of this, referring to Picard, Ber- 

 noulli, Romberg and Hauksbee. 



(2) Artificial phosphori require some sort of preparation. Such 

 are {a) the burning phosphorus (also called Kunkel's phosphorus 

 and phosphorus fulgurans) , (/;) the Bononian phosphorus, and (c) 

 the Balduinian or hermetic ^^ phosphorus. 



Chambers described the preparation of the Bononian and Bal- 

 duinian phosphors and gave the following 



Rationale of the effects of phosphorus. It may be observed that in most 

 of the natural phospJiori, there is a brisk attrition or friction concerned; 

 which we may suppose either to give the minute parts of the substance 

 the proper motion and agitation necessary to convert them into fire, if 

 fire be so producible, (as Bacon, Boyle, Newton, and the generality of 

 the English philosophers have supposed it is) or to expel and emit the 

 particles of fire naturally contained in them. See fire, flame, friction, 



ATTRITION, &C. 



In the factitious sorts, we may note, that a long process by fire is 

 usually required wherein the matter undergoes divers coctions, torre- 

 factions, calcinations, distillations, &c. in the course whereof a con- 

 siderable quantity of fire must necessarily be imbibed, and may possibly 

 be retained therein. 



The word " Noctiluca," as defined by Chambers, applied to " a 



^^ So called because the German chemist Baldouin was referred to as Hermes in the 

 Society of the Naturae Curiosum. 



