SCIENTIFIC SUMMARY. 
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thing very like a fiction, and that very few are exactly of the same 
brilliancy. Should the amateur arrange the stars visible without a tele- 
scope according to their brightness he would discover another remarkable 
phenomenon, — viz., that the stars are not equally constant in their light, 
but that many have been discovered to be variable; and it is very probable 
that many more remain to be detected, even of those visible to the naked 
eye. Thus, Beta of the constellation Perseus varies from the second to the 
fourth magnitude and back again in less than three days ; Lambda Tauri 
changes nearly a magnitude in four days ; Eta Aquilse, in seven days ; 
Zeta Geminorum returns to the same brilliancy every ten days ; Beta 
Lyrse falls from the third to the fourth class, with singular changes of 
light, and returns to its original lustre every thirteen days ; Alpha Herculis 
passes from the third to the fourth magnitude, and back again to the third 
every sixty-three days. Chi Cygni is visible to the naked eye at its 
brightest epoch, and almost unseen in the most powerful telescopes at its 
faintest time ; it has a period of .397 days. In addition to those stars (all 
of which are easily found by help of a map of stars or a celestial globe), 
there are others which are visible at the present time, and on which many 
valuable observations might be made with unassisted vision, such as 
Epsilon Aurigse, Alpha Orionis, Alpha Ursse Majoris, EtaUrsse Majoris, 
Alpha Cassiopeiae, and Alpha Hydrse. Perhaps the most remarkable of 
all the variable stars is Omicron, or Mira Ceti, as it has been called, which 
has a period of 332 days. It is one of the brightest stars in the constella- 
tion of the Whale at its maximum brilliancy, being frequently, though 
not always, at that time of the second magnitude, whence it becomes 
completely invisible. Although favourably situated at present, it is now 
invisible without the assistance of a telescope, having arrived at its greatest 
brilliancy at the commencement of August, and being only visible to the 
naked eye for about 130 days. In addition to those objects, there are 
upwards of fifty well-determined telescopic stars which vary in lustre, 
more or less, and of which the following can be observed at present by 
those who possess telescopes : — T Hydrse (R.A. 8h. 48m., Dec. 8° 37'), 
with a period of 292 days, varying between the eighth magnitude and 
invisibility, arrives at its probable greatest brightness on Feb. 22, 1862 ; 
U Yirginis (R.A. 12 - 44, Dec.-J-6°19') will probably arrive at its maximum 
magnitude of the seventh order of brightness on Jan. 4, 1862 ; S Tauri 
(R.A. 4h. 21m., Dec. 4-9° 38') will become visible on March 11, in good 
telescopes, when it arrives at its greatest lustre of the tenth magnitude. 
S Yirginis (R.A. 13h. 25m., and Dec. 6° 28') has a period of 368 
days, and may probably become visible to the naked eye on May 15. 
R Tauri (R.A. 4h. 21m., Dec. -(-9° 51') varies between the eighth magni- 
tude and invisibility, will arrive at its maximum on May 7. U Capricorni 
(R.A. 20h. 40m., Dec. 15° 17') with a jJeriod of 412 days, arrives at its 
maximum of tenth magnitude at the end of February, 1862. These, of 
course, are only a sample of the riches of this class of objects, and the 
amateur will find much pleasure in following up and noting their changes. 
And although he may not find the winter temperature very agreeable, 
still, however, our insular temperature will not descend to the degree of 
cold noted by Winnecke, whilst observing the variable stars last winter 
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