I885-J 
Variable Stars. 
43 
which are observable in the un-uniform and erratic changes 
which v Argus undergoes. It has vied in brilliancy with 
Sirius, although there have been times when it has been 
scarcely conspicuous upon the background of the sky. At 
the same time it is necessary to remark that opinion differs 
as to whether the star is really within the nebula or dis- 
sociated from it. The question will never, probably, be 
diredtly determined, although it seems difficult to examine 
Herschel’s drawing of the nebula and then conclude that 
the stars in the same field are merely superposed upon it. 
If the star is in the nebula, my view is, of course, greatly 
strengthened ; if it is not, the theory cannot be regarded as 
thereby weakened appreciably. All that need be said is 
that the changes of v Argus are of better probability when 
ascribed to a meteoric origin than as a planetary phe- 
nomenon, and that its position would seem to supply the 
clue as to the source from whence its energy is derived. 
Accepting the meteoric theory as true, we may divide the 
stars into three classes as follow : — 
a. Those whose meteor systems are fixed, and not subject 
to any considerable changes. To this class belong the Sun 
and Algol. 
f3. Those whose meteor systems have definite orbits, but 
of such a richness that a considerable quantity must from 
time to time fall upon their sun’s globe in the manner 
described above. To this class belong such stars as Mira 
and »? Argus, which possibly represent a state of things 
through which our own sun has long since passed. 
7 . Temporary stars. 
Upon this theory the phenomena of temporary stars 
could be considered as caused by an accidental collision in 
space between the matter of which the Milky Way is largely 
made up and the stars whose sudden appearances have from 
time to time astonished the world of science; or, in short, 
that variable stars represent the manifestations of purely 
local movements, whilst temporary stars point to the adtion 
of matter foreign to their systems. Moreover, the stars 
themselves are in motion, and it only requires that them- 
selves and the matter with which they collide should be 
travelling in the right direction to ensure a collision. Nor 
must it be forgotten that the Solar System is liable to the 
same catastrophe, which, if it ever occurs, will most cer- 
tainly sweep every vestige of life from the surface of the 
earth. But, comparing the Sun’s position in space with 
those suns whose light reaches us from the depths of the 
Galaxy, and, further, taking into account the rarity of the 
