[ 2 &6 ] 
nothing of what had happened, was a real found, and 
immenfely greater than any we arc acquainted with. 
For, at the diftance of 70 miles and upwards, it was 
compared to loud thunder, the report of heavy artil- 
lery, the fall of the gabel- end of the houfe the perfon 
was in, and to a mufket fired off in the garret. If 
this noife was produced when the body threw out 
thofe maffes of burning matter (by the obfervers 
called fparks of fire, the burfiing of the tail, and de- 
lineated in Fig. 7. as balls of a fmaller fize in the 
train itfelf), we fhall find, that at this time the me- 
teor, by being more than 41 miles high, was in a 
region where the air is three thoufand times rarer 
than on the furface of the earth ; that is, about fix: 
times rarer than in a -common exhaufted receiver, 
where fonorous bodies are not heard, and even where 
gunpowder and the pulvis fulminant take fire, and 
are exploded, but without noife. Hence I would 
infer, that the feparation of the elaftic matter muff 
have been performed with a velocity exceeding ail 
imagination ; as the intenfity of found fo much 
depends on the reftftance of the air, and as this ela- 
ftic matter could fly off with fo much celerity, as to 
find fo great an oppofition from fo thin a medium *. 
. I fhould alfo conclude from the great report, that 
the fubftance of the meteor was of a firmer texture 
than what could arife from mere exhalations, whe- 
ther formed into a fphere, and then burning ; or dif- 
* M. Suluce has lately fhewn, by fame curious experiments, that 
fuch fubftances as gunpowder and the pulvis fulminans, have a de- 
tonation in proportion to the rapidity with which the internal air 
is fcparated, and to the refinance of the external air. See Mi f cell. 
Taurimns, Torn, I. 
pofed 
