A CATALOGUE OF OBSERVATIONS OF LUMINOUS METEORS. 39 



The time when most meteors are seen would probably also be the time 

 when we should observe them most nearly moving at right angles to their 

 true directions. 



a.mG]Easil 



z" observer's zenith. 



0, observer. 



B. Olmsted, in his ' Mechanism of the Heavens,' a popular little hand-book, 

 gives a diagram (fig. 2), the object of which is simply to show the reason 



Fig. 2. 



Let ABC be the vault of the sky, and the observer. Let 1, 2, 3, 4 represent par- 

 allel lines towards the earth. A meteor passing through I'l, or axis of ■vision, would appear 

 stationary at 1'. A body falling at 2 2 would seem to describe the short arc 2' 2', or a 

 concave path in the sky ; and similarly a body falling through 3 3 would appear to describe 

 the larger arc 3' 3', &e. Hence those meteors which fall nearer the axis of vision would 

 describe shorter arcs, and move slower, while those further from the axis and nearer the 

 horizon would seem to describe larger arcs, and move with greater velocity. The meteors 

 would all seem to radiate from a common centre 1', which was the case on Nov. 13th, 1833. 



why there should appear to be a radiant point for shooting-stars, and why near 

 that point in the heavens no meteors or very few were seen, or if seen why 

 their tracks near that point appeared so short, and in other parts longer (and 

 why perhaps also, on the principle of fig. 1, more numerous towards the east). 



