74 Objervations on Fire Balls. 



their aclual height; as, according to the meafurcment of 

 Bergman, Kaftner and Lambert*, the northern lights have 

 an altitude of more than 20 or 30 German miles, and ac- 

 cording to every appearance no fire-balls have been feen 

 higher. On the other hand, this general conclufion led 

 Halley f , Franklin J, and Rittenhoufe §, to the grand idea, 

 which Dr. Chladni has defended with fo much ingenuity, 

 that theie phenomena, as well as fhooting ftars, are cofmical 

 meteors belonging to the atmofphere of the fun, which 

 meeting our earth in its courfe round that luminary are 

 inflamed, by fome caufe or other, when they enter the 

 earth's atmofphere. The phenomenon alfo feen by De 

 Genflance at Paris in the month of July 1738, and the 

 like obfervation of falling ftars on the higheft mountains, as 

 well as on the furfacc of the fea ||, but in particular the new 

 diftant luminous phenomenon obferved by M. Schroter f , 

 will appear the more favourable to this hvpothefis, as we have 

 reafon to fuppofe that there are proceflcs carried on in our 

 atmofphere with which we are as little acquainted as with 

 thofe carried on in the interior parts of the earth. 



15. The time of their duration was very different : that 

 obferved by De Genflance continued half an hour; at other 

 times their duration has feldom been above a minute. Few 

 or none of them, however, have been obferved from the 

 commencement of their appearance till the time when they 

 difappeared. 



16. Many of them in their courfe threw out fparks, and 

 the greater part of them were feen to divide themfelves into 

 leveraljlbmetimcs larger, fometimes fmaller parts, before they 



. • Gottingifcher Tafchen-Calendar, 1778, p. 52. 



■\ Philofoph. Transitions, No. 341. 



{ Gothaifches Magazin, vol. iv. pare 2. p. 114; and vol. ix. parr 3. 

 p. 173. 



§ Tranfailions of the American Philofoph. Society, vol. ii. p. 175. 



|| Brydone in the Philofoph. Tranfaclions, vol. lxiii, part 1. p. 167. 



S[ Gothaifch.s Magazin, vol. xi. part 1. p. 86> 



entirely 



