Virginia citizen. (Irvington, Va.) 1891-1921, 1910-04-08

eaoh Woo uiouc oH ndiSy COtneI iIocih
in 1885 by Struve at Dorpat and by Glai-
sher in England, and more recently still
on December 5th last by Herr .Archen-
hold, of the Treptow Observatory, Ber-
lin, who saw the comet pass before q
very pale star of the twelfth magnitude
without altering its light or its color.
We may conclude then that the sun will
not undergo any change or any appre-
ciable weakening from the fact of the
comets passage.
Nevertheless, it may he that among
these meteors there are some very
large ones and we ought to take advan-
tage of the exceptionally favorable ap-
proach of the comet to endeavor to
measure the size of these blocks. 1t is
admitted that there can be distinguish
ed dark spot of tenth of second in
diameter standing out from the back
ground of luminous disk.
AT the distance of the comet on May
18th, that is to say, twenty-three mil
lion kilometres, we might be able to see
any opaque body measuring about 112
kilometres in width. We can hardly
hope to discover solid masses of such a
size in the nucleus, but it would be in
itself an important result to learn with
certainty that there do not exist pro-
jectiles so enormous in a comets head.
1t will be for the astronomers stationed
in the far East toundertake this search,
for they will be in the best condition
to follow the passage of the comet in
broad daylight.
For European Observers.
European observers may see the tail
cross their sky in the night of May Is
to 19, about two O'Clock in the morning.
Paris time. However, the exact hour
will depend on the length of the tail at
that moment and also its form. If it is
slightly curved we will pass its axis a
little latter. The combined speed of the
earth and of the tail at the moment of
meeting will be 1900 kilometres e, ,S75
miles) a minute, or 276, 900 kilometres
Q72, 500 miles) an hour. If observations
can be made under good atmospheric
conditions they will show us whether
the tail is hollow or full. elliptical or
circular in the plane of it's section or,
what is more probable, whether it is of
irregular construction.
If it be admitted that this caudal ap-
pendage is exclusively composed of
electrified gaseous molecules, very far
apart one from the other, with which is
mingled minute cosmic dust in insignifi-
cant quantity, the number of shoot
stars which will appear on this famous
night will not be as considerable as one
might imagine. 1t is especially about
May 6 that they should appear, when
we will arrive in the vicinity of the
comets orbit. But we will doubtless
witness some effect analogous to that of
June 80, 1861. On that date it seems
very probable that the earth traversed
the tail of comet, an event which,
moreover, passed unperceived by the
majority of the inhabitants of the ter
restrial globe.
We see that If things pass as in 1886
it may be possible that the tail will not
reach our world. because it will disap-
pear after the perihelion passage, which
will take place on April 20. On the
other hand. Mr.. Barnard, the astrono-
mer, of the Yerkes observatory, has al
ready measured the length of the
present tail, on February 3 and Febru-
ary 10. and has found that length to be
5000, 900 kilometres. On the same dates
the width of the head was S07, OOO
kilometres. The same astronomer re-
marks as to this fact that the consider
able extent of the tail two months
before perihelion ''gives hopes" that
we will be completely immersed in that
appendage on the date of May Is.
He who lives will see.