the Lighi of Bodies in a Slate of Comhujlion. ipp 



other. The fluid in pafling through the interval which fepa- 

 rates the wires is always luminaus, if a force he uied fuffi- 

 ciently ftrong. I fhould obferve, that the ghifs tube, if not 

 very thick, always breaks when this experiment fucceeds. To 

 make the pafiage of the fluid luminous in the acids, they mufl 

 be placed in capillary tubes, and two wires introduced, as in 

 the preceding experiment, whofe points lliall be very near each 

 other. It is a well known fadl, that the difcharge of a fmall 

 Leyden phial in paffing over a flrip of gold, filver, or Dutch 

 metal leaf, will appear very luminous By conveying the con' 

 tents of ajar, measuring two gallons, over a ftrip of p-old leaf 

 one-eighth of an inch in diameter, and a yard long, I have 

 frequently given the whole a dazzling brightnefs. I cannot 

 fay, that a much greater length might not have been made 

 very fplendid, nor can I determine- to what length the 

 force of a battery might be made luminous in this manner. 

 We may give this experiment a curious diverlity, by laying 

 the gold or filver leaf on a piece of glafs, and then placing the 

 glafs in water; for the whole gold leaf will appear moft bril- 

 liantly luminous in the water by expofing, it, thus circum- 

 flanced, to the explofion of a battery. 



2, The difficulty of making any quantity of the eleflrlcal 

 fluid luminous in any body increafes as the conducing power 

 of that body increafes. 



EXP. I. In order to make the contents of a jar luminous 

 in boiling water, a much higher charge is neceflary than would 

 be fufficient to make it luminous in cold w^ater, which is uni- 

 verfally allowed to be the worft condudlor. 



EXP. II, I have various reafons for believing the acids to 

 be very good condu£lors. If therefore into a tube, filled with 

 water, and circumflanced as I have already defcribed, a few 



drops 



