128 NOVUM ORGANUM 



generally at the time of the greatest heats. The appearances 

 we term falling stars are generally supposed to consist of 

 some shining and inflamed viscous substance, rather than 

 of violently hot matter; but let this be further investigated. 



Some coruscations emit light without burning, but are 

 never accompanied by thunder. 



Eructations and eruptions of flame are to be found in 

 cold climates as well as in hot, as in Iceland and Greenland; 

 just as the trees of cold countries are sometimes inflammable 

 and more pitchy and resinous than in warm, as the fir, pine, 

 and the like. But the position and nature of the soil, where 

 such eruptions are wont to happen, is not yet sufficiently 

 investigated to enable us to subjoin a negative instance to 

 the affirmative. 



All flame is constantly more or less warm, and this in 

 stance is not altogether negative; yet it is said that the ignis 

 fatuus (as it is called), and which sometimes is driven against 

 walls, has but little heat; perhaps it resembles that of spirits 

 of wine, which is mild and gentle. That flame, however, 

 appears yet milder, which in some well authenticated and 

 serious histories is said to have appeared round the head 

 and hair of boys and virgins, and instead of burning their 

 hair, merely to have played about it. And it is most cer 

 tain that a sort of flash, without any evident heat, has some 

 times been seen about a horse when sweating at night, or in 

 damp weather. It is also a well known fact, 19 and it was 

 almost considered as a miracle, that a few years since a 

 girl s apron sparkled when a little shaken or rubbed, which 

 was, perhaps, occasioned by the alum or salts with which 



9 Was it a silk apron which exhibited electric sparks ? Silk was then 

 scarce. 



