VOL. XXXI.] PHILOSOPHICAL TRANSACTIONS. 455 



symptoms. That generally, however, the most cordial medicines should be 

 exhibited as early as possible, and in large doses ; that all evacuations, except- 

 ing that of perspiration, should be avoided; that, when they come on sponta- 

 neously, they should be checked by the remedies adapted to each ; thus a diar- 

 rhoea has been stopped by an astringent clyster, to which some theriaca was 

 added. That, where watchfulness takes place, the spirits should be calmed 

 by the exhibition of opiates; that, on the other hand, where stupor and lan- 

 guor prevail, the spirits should be roused by volatile and camphorated medicines; 

 that a due consistence of the blood should be preserved in the advanced stage 

 of the disorder by the use of acids and the astringent earths ; that the poison 

 should be diverted to the surface of the body, &c. 



An Account of a Luminous Appearance in the Air at Dublin. By Philip 

 Percival, Esq. N° 364, p. 21. 



Jan. 12, 1719-20, was observed an odd appearance in the sky about 10 

 o'clock. But it had nothing very remarkable till about half an hour after 1 1 , 

 when I was called out to see it, by the servants, who had been looking at it 

 about half a quarter of an hour, and said it looked just like fire. But it ap- 

 peared at first to me in long streams of light, of a round body, as at a, fig. 15, 

 pi. 10, and very bright, though some were coloured, as at Aa. They came 

 i)efore the wind, which was then west, as near as I could guess, there not 

 being a cloud in the sky, and the brightest moon I have known. We had 

 rain about 5, but at 6 o'clock the night was clear. The streams of light, aa, 

 moved very slowly, there being but little wind, but as they moved they joined, 

 and, swelling out in the middle, formed themselves into the figure bbfi, con- 

 tinuing to advance slowly in that shape for about a minute, when the two ends 

 bb, approaching near each other, as described by the pricked lines, the advanced 

 part B ran suddenly back, and joining itself with the ends bb, formed itself 

 into the figure c, quivering in the upper part, and darting down perpendicularly 

 in sharp points, as at ddd ; and its colour, from a bright light, changed into 

 the colours of a rainbow, but much fainter. It continued this way about a 

 minute, and then the sharp points ddd, gathering themselves up into c, it 

 changed again into a square sheet of light, as at e, and swelled out at p, as 

 before at b ; then advancing leisurely, it repeated the same scene as before, 

 till it seemed at a great distance to disperse itself into small thin light clouds. 

 I was very particular in observing it, and the next morning drew it, and I 

 think very exactly. The beginning of it was very like the aurora borealis, 

 which has been very frequent here this winter. 



