1867.] Astronomy. 227 



the meteors were increasing their distance from the sun, while the 

 reverse would have been shown if the radiant-point had been on 

 the right. If we attach equal value to each of the determinations 

 indicated in the figure, we must take as the mean position of the 

 radiant a point not appreciably removed from the dotted line. 



It follows that, either the orbit in which the meteoric zone 

 or flight travels, is nearly circular, or (which seems less proba- 

 ble) that the descending node of the orbit coincides (very nearly) 

 with its aphelion or perihelion distance. Assuming an orbit very 

 nearly circular, we must assign to the meteors a period not differ- 

 ing by many days from that of our own earth. To account 

 further for the period of thirty-three years, which separates suc- 

 cessive recurrences of maximum intensity, we must have a period 

 either exceeding or falling short of one year by about l-33rd 

 part, that is, by about eleven days. If we accept Ertel's view 

 that the three cold days in May are due to the interposition 

 of the meteor-zone between the earth and sun, we must suppose 

 the mean distance of the meteors from the sun to be less than the 

 earth's mean distance, and therefore we must take the shorter 

 period, about 354 days. All the circumstances of the zone's motion 

 may be determined with these data, and nothing is wanting but 

 exact observations of the velocity with which the November me- 

 teors traverse our atmosphere, to establish Professor Newton's 

 views on a sure basis. Professor Adams has gone through the 

 requisite calculations for obtaining the approximate elements of 

 the orbit ; but confirmatory observations are as yet wanting. 



Our readers are not to understand, however, that any doubt 

 remains respecting the planetary motions of meteors. The mere 

 mathematical evidence afforded by their apparent motions is 

 sufficient to establish this point on as sure a basis as that of 

 the Copernican theory itself. All that remains in doubt is the 

 exact form and position of the orbit described by the meteor 

 flight around the sun. 



The observations made at the Cape Town Observatory are 

 worthy of careful examination. Briefly, they amount to this : — 

 The display was well seen, but not quite so rich as in Eng- 

 land; the time at which the shower reached its maximum was 

 about 2h. 10m. a.m., Cape Mean Time, corresponding to about 

 1 a.m. Greenwich time; so that the display there reached its 

 maximum about ten minutes or a quarter of an hour earlier 

 (as to absolute time) than in England, where 1 h. 15 m. was 

 noted as the hour of maximum intensity; at Cape Town, as 

 in England, the period during which the display lasted (in a 

 marked form) was about 2^ hours. To interpret these results 

 we must form a conception of the earth as it was actually situ- 

 ated during the night of November 14th. An observer placed 



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