86 



REPORT 1879. 



orbit are thence deduced, are as follows, taking the real duration as 

 fifteen seconds. (The elements of the orbit of Biela's comet at its last 

 appearance in 1852 are added in a contiguous column for comparison.) 



' The precise Greenwich time of the occurrence of the meteor was 

 10 b 26 m . 



' If the duration of visibility is diminished to 7^ seconds, the elements 

 are still very similar to the above, the semiaxis major becomes 1'3785, 

 and the period 591 days. Captain Tupman remarking that such favour- 

 able conditions for inferring the orbit of a meteor very rarely happen, 

 adds, it is sufficient for the establishment of a short periodic time (such 

 as 500 days) that " the meteor moved slowly from a fairly well-deter- 

 mined radiant distant about 90° from the point of the heavens towards 

 which the earth's motion was directed." 



' We may mention that there is one singular circumstance not alluded 

 to in Captain Tupman's note : the elements defining the position of the 

 orbit of the meteor have a striking general resemblance to those of the 

 orbit of Biela's comet, in the descending node of which body the earth 

 was precisely situated at the time.' 



With sufficient allowances for possible perturbations and retardations 

 of its course by earlier encounters with the earth, it seems extremely 

 probable that the calculated real orbit of this remarkable and unusual 

 fireball may not be irreconcilable with its original derivation from the 

 Biela meteor stream. 



The observations of the second fireball of January 12 last, in Bohemia, 

 all described a meteor moving nearly from S. to N., with a large disc of 

 bluish- white light casting a strong illumination like that of moonlight 

 on all objects. Exact particulars of its direction were obtained from eight 

 stations near Salzburg, in the south, to Zittau, on the Bohemian frontier 

 of Saxony in the north, showing that its real path instead of crossing the 

 middle of Bohemia, as that of the first did, almost horizontally from east 

 to west, traversed the western part of Bohemia with a rather steeper descent 

 from south to north, crossing the northern frontier of the country at last 

 into Saxony. It terminated here at a probable height of about 23 miles 

 over Grossenhain, a point at a little distance N.N.W. from Dresden, where 

 it arrived by a flight of 130 miles, descending from alt. 28°, 9° E. from 

 S. at a height of about 78 miles over the neighbourhood of Pibram in 

 the south-western part of Bohemia. At a height of about 40 miles, near 

 its passage across the Saxon and Bohemian frontier, the nucleus divided 

 or was partly extinguished at its maximum, a much smaller luminous 

 body only pursuing the same course farther to the point of disappearance. 

 No sound of this explosion or of any other disruptions along its course 

 appear to have reached observers who were most favourably situated by 

 their closeness to the lowest and most brilliant portions of its flight for 



