~~ 
and parallel with the horizon. Its velocity was thirty miles — 
230 On the Meteor of May 18th, 1838, 
o’clock in the evening where the meteor was vertical. The point 
then towards which the earth’s motion was directed, ‘had: passed 
_ by nearly two hours the inferior meridian. 'The line of direction 
was inclined to the horizon about 52°, and its azimuth was 
somewhat east of north. ‘The meteor’s course was nearly north 
per second; that of the earth 19 miles. The directions of the 
earth and meteor were inclined to each other about 64°, and the 
meteor’s velocity of thirty miles was its velocity relatively to the 
earth. It is then simply a mathematical question to determine 
what must have been the absolute direction and velocity of the 
meteor’s motion, in order that, combined with the earth’s motion, 
it may give the above Seealtant, The velocity I find to be about 
forty miles per : second. A part of this velocity, less however than 
seven miles, was due to the earth’s attraction. We must then 
admit that a small collection of exceedingly rare matter, revolv- 
ing about the sun in an orbit which at one point coincided nearly 
with that of the earth, but moving with about double the velocity, 
plunged into the earth’s atmosphere, took fire, and exhibited the 
splendid phenomenon of May 18. hat no portion of this body 
escaped from the earth’s atmosphere and continued its solitary 
route, we cannot positively affirm ; although the appearances seem 
to favor the supposition that the body was quite consumed in our 
atmosphere. 
For the curvature of the meteor’s path we can perhaps give 
only a hypothetical explanation. When a ball is moving with 
great velocity through the air, if one side be of such a form as to 
experience greater resistance than the opposite, it will be rela- 
tively retarded, and the path of the body will deviate towards 
that side.. Now as it is highly improbable that the opposite sides — 
of the meteor should be perfectly symmetrical, it might be eX-~ 
pected to deviate more or less from a straight line. Moreover, 
the progress of the meteor was marked by combustion, which 
may be supposed to have been attended by a copious evolution of 
gas. Now if this gas should be evolved upon one side of the me- 
teor more abundantly thar on the other, it would become a moving 
force, which by reaction would cause the meteor to deviate to the 
— side. As these two causes appear to me highly probable, 
and adeg ite to account for the phenomenon, I think it superflu- 
earch for others. The earth’s attraction would hardly 
th-part of the deviation from a — line 
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