THE LOST COMET AND ITS METEOR-TKAIN. 
145 
produced by bodies which were travelling in the track (speaking 
generally, hien entendu) of Biela’s comet. It is sufficient to 
compare the position of the radiant point with that which 
would have been due to meteors following precisely in the 
orbit of Biela’s comet, as calculated for the last perturbed 
epoch, 1866. Mr. Hind, the superintendent of the “Nautical 
Almanac,” has calculated for the radiant point due to the 
comet a place in E. A. 1^. 41™., and N. P. D. 48°. We have 
seen that Professor Grant gives for the observed radiant point a 
position in E. A. 26° (or 1^. 44™.), and N. P D. 44°, a singularly 
close agreement under the circumstances.* 
But now comes the most singular part of the whole affair. 
It occurred to the German astronomer Klinkerfues that if 
search could be made in the part of the heavens directly oppo- 
site to that whence the meteor-shower had appeared to radiate, 
the cluster of meteoric bodies which had produced the display 
might be detected. In fact, Klinkerfues appears to have sup- 
posed that Biela’s comet had itself touched the earth on the 
evening of November 27, for he telegraphed to Mr. Pogson 
(the Government astronomer at Madras) in the following 
terms: Biela touched earth on 27 th; search near Theta 
• In passing I would venture to touch on what I cannot hut regard as an 
error in the treatment of this subject by Professor Newton of America, and 
some other astronomers. They attribute to the indications of the meteoric 
paths a degree of accuracy which cannot, I conceive, be regarded as to be 
depended upon. And where, judging from the meteoric motions, the radiant 
seems to shift in position, or to occupy an area rather than to be a mere 
point, they deduce such and such inferences from one or other circumstance. 
But it must be remembered that apart from those causes which would tend 
to spread the radiant region, the meteors must by the action of the atmos- 
phere be very often, if not always, caused to deviate from the direction in 
which they had been moving before they reached the upper limits of the 
atmosphere. We cannot assume that because the air is very rare where the 
meteors first become visible, they therefore encounter an inappreciable resist- 
ance. The very fact of a meteor becoming visible shows, on the contrary, 
that there has been a degree of compression of the atmosphere in front of 
the meteor, which must necessarily involve a considerable resistance. And 
it is utterly unlikely that this resistance should take place without to some 
degree afiecting the direction in which the meteor travels. Nor will all 
meteors be alike affected. For it is to be remembered that of the meteors 
seen from any given station some strike the atmosphere in a very different way 
than others. Some impinge almost squarely upon the upper atmospheric 
layers, while others fall much more aslant. Then there must often be a 
difference of density and of arrangement in the upper strata of our atmos- 
phere. These and other causes which may be pointed out, as well as 
differences in the size, weight, and density of the individual meteors, must 
lead to appreciable changes in the direction of motion. 
VOL. XII. — NO. XLVII. L 
