140 Meteoric Astronomy. [April, 
August system which actually encounters the earth must reach 
the earth’s globe from one and the same direction inspace. If 
the earth were actually at rest, the meteors of this system 
would seem to fall like a shower coming from a definite 
quarter. This, indeed, might not appear to be the case to 
observers occupying a particular point on the earth’s surface, 
—simply because the meteor-shower would be only partially 
discernible by him, and the circumstances would be such as to 
cause some illusion as to its origin and nature. But if we 
regard the earth as a whole,—and for a moment as a 
sentient being,—it will be obvious that, supposing she were 
at rest, she would seem to be exposed to a meteoric shower, 
many meteors falling upon her and yet larger numbers 
passing by her, but all appearing to come from the same 
quarter. But taking her orbital motion into account, we 
obtain a precisely similar result, only the direction of the 
shower becomes modified. ‘The case may be compared to 
that of a railway carriage in a steady shower of rain; such 
a shower will appear steadily to proceed from one quarter of 
the sky whether the carriage isat rest or moving uniformly in 
a given direction. Only in the latter case, the part of the 
sky from which the shower seems to proceed will seem to be 
somewhat nearer to the point of the horizon towards which 
the train’s motion is carrying the carriage. So with the 
earth passing through a meteor stream ; the meteor-shower 
will seem to fall from one and the same part of the celestial 
sphere though the earth is travelling rapidly onwards; only 
the part of the heavens from which the shower seems to 
proceed will seem to be somewhat nearer to the point 
towards which the earth’s orbital motion is carrying her 
than in the imaginary case of a fixed earth exposed to the 
continuous downfall of the meteors belonging to the August 
system.* But in either case the shower will seem to come 
from a determinate point of the star-sphere enclosing the 
earth on all sides. 
Similar remarks apply to the November shower. 
* In considering this matter we need not concern ourselves with questions 
of perspective, which, though commonly introduced to explain the subject, 
tend rather to perplex than to enlighten the learner. The case is exceedingly 
simple in reality :— ; 
Thus, let Ee, Fig. 1, be a small part of the earth’s orbit at the place where 
any meteor system is encountered, and let Mm indicate a portion of the meteor- 
orbit, ME’ being the course traversed by a particular meteor while the earth is 
moving along E£', so thatthis meteor encounters the earth when she has 
arrived at E'’.. Then to the observer on earth, unconscious of the motion from 
E to E', the course on which the meteor seems to arrive is obviously in the 
direction of a line from Mto £, so that a line, m’, parallelto ME is the seeming 
path of the meteor’s arrival; and a point s’ on the celestial sphere, in the 
