418 
POrULAR SCIENCE REVIEW. 
two distinct comets. Now some ten or twelve months after the comet had 
(according to the calculations of astronomers) passed the part of its orbit 
which intersects the earth’s track (or at least passes very close to it), the 
earth herself came to the corresponding part of her orbit — that namely 
which she passes on or about November 26, 27, and 28. There then occurred, 
as had been predicted by Professor Alexander Herschel, a shower of meteors, 
in which some tens of thousands of small shooting stars were seen, radiating 
from a part of the heavens near the feet of Andromeda, and thus corre- 
sponding with the course which bodies following in the track of Biela’s 
comet would pursue on the sky if they entered the earth’s atmosphere when 
she is in the part of her orbit crossing Biela’s. Klinkerfues, assuming that 
this cloud of meteors was Biela’s comet itself, telegraphed to Mr. Pogson, 
Government Astronomer, at Madras, to examine the part of. the heavens — 
near Theta Centauri — towards which the meteors were moving. Pogson 
did so,* and saw in that part of the heavens two cloud-like objects moving 
along a course corresponding with that which attendants of Biela’s comet 
would have followed as viewed from the earth. Now Mr. Hind, in discuss- 
ing the question of the possible rediscovery of Biela’s comet, takes as a 
probable assumption that the comet really touched the earth on November 
27, 1872. “ Intersecting, or at least passing very near to, the earth’s orbit, 
on November 27,” he says, “ the comet must have been descending to a 
perihelion passage a month later, or about December 27*6; such at least 
would be the date when the meteoric shower would arrive at its least dis- 
tance from the sun. In this fact appears the only ground upon which we 
can now work to obtain an idea of the probable position of the comet in the 
present year.” Then, having given the most probable elements of the orbit 
of Biela’s comet as determined from the observations of 1846 and 1852, he 
says that if the meteoric cloud of November 27, 1872, was moving in this 
orbit, “ a revolution counted from December 27*6 in that year will bring us 
to about September 8, 1879, as the epoch of next perihelion passage. As- 
suming September 7*5, we should have the following sweeping-line for that 
date : — 
Time from 
Right 
North 
Distance 
Intensity 
perihelion. 
Days. 
ascension. 
o 
declination. 
O 
from earth. 
of light. 
0 
140-2 
10-8 
1-66 
0-47 
-20 
125-9 
17-4 
1-42 
0-57 
u It may, however,” he proceeds, “ be regarded as by no means impro- 
bable that the perihelion passage of the body which caused the shower of 
meteors may take place much later, and a very close and extended search 
will be required.” 
It should be noted, however, that the display of meteors seen on Novem- 
ber 27, 1872, was by no means such as to suggest that the cloud of meteo- 
rites would be discernible as a nebulous object by reflected light. Again it 
seems certain that the two nebulous objects seen by Pogson, were not travelling 
as that meteoric cloud would have travelled ; this was very clearly and satis- 
factorily shown early in 1873 by Captain Tupman. And if we suppose that 
either Pogson’s nebulous clouds, or the meteoric flight, were Biela’s comet, 
the delay of ten or twelve weeks is quite inexplicable by any possible per- 
turbation, seeing that a cause effective enough to have made a difference of 
