VOL. XLIII.] PHILOSOPHICAL TRANSACTIONS. 137 



strange flashing of sparks, seemed to be of Arc, in all the wearing apparel she 

 put on, and so continued till Candlemas: and, in the company of several, viz. 

 Captain John Harris, Mr. Edward Braines, Captain Edward Poulson, &c. the 

 said Susanna did send several of her wearing apparel, and, when they were shaken, 

 it would fly out in sparks, and make a noise much like unto bay-leaves w hen 

 flung into the Are; and one spark fell on Major Sewall's thumb-nail, and there 

 continued at least a minute before it went out, without any heat, all which hap- 

 pened in the company of Wm. Digges." 



* " My Lady Baltimore, her mother-in-law, for some time before the death 

 of her son, Cagcilius Calvert, had the like happened to her; which has made 

 Madam Sewall much troubled at what has happened to her. 



" They caused Mrs. Susanna Sewall one day to put on her sister Digges's 

 petticoat, which they had tried beforehand, and would not sparkle; but at 

 night, when Madam Sewall put it off, it would sparkle as the rest of her own 

 garments did." 



Bartholin of Copenhagen, in his collection of anatomical histories that are 

 unusual, century 3, hist. 70, which he entitles Mulier Splendens, gives a parallel 

 instance in a noble lady of Verona in Italy, which he says he had from an account 

 of the phenomenon published by Petrus a Castro, a learned physician of the same 

 place, in a small treatise intitled De Igne Lambente. 



, There is another author. Dr. Simpson, who published a philosophical dis- 

 course of fermentation. Anno 1675, who takes notice of light proceeding from 

 animals, on their frication or pectation, as he calls it; and instances in the 

 combing a woman's head, the currying of a horse, and the frication of a cat's 

 back, the last two of which are known to most. According to this gentleman's 

 hypothesis, he would assign the principles of fermentation, which he supposes 

 to be acidum et sulphur, as the cause of these lucid effluvia in animals. But 

 more probably the properties of the effluvia in animal bodies are many of them 

 common with those produced from glass, &c. : such as their being lucid, their 

 snapping, and their not being excited without some degree of friction, and elec- 

 tricity , for a cat's back is strongly electrical when stroked. 



In the account of some of the earlier electrical experiments made by Mr, 

 Gray, Phil. Trans. N° 366, we are informed, that he electrified several other 

 bodies, besides animal substances, by drawing them between his thumb and 

 fingers; in particular, linen of divers sorts, paper, and fir-shavings, which would 

 not only be attracted to his hand, but attract all small bodies to them, as other 

 electric bodies do. Now, notwithstanding this last circumstance of their at- 

 tracting as well as being attracted, may it not be questioned, whether, in this 



• The additional lines are not in Colonel Digges's hand, but seem to be in Mr. Clayton's. — Orig. 

 VOL. IX. T ' ' 



