4 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



Mr.Plummer lias a note on the collective light distribution 

 of the fixed stars. lie finds that fully three fourths of the 

 light of a fine night comes from stars which are individually 

 invisible to the naked eye, and that on his hypothesis the 

 total light of all the stars of the Durchmusterung is equal 

 to 10.17 x Venus at maximum brilliancy, or l-f-78.6 of the 

 mean full moon. His final conclusion is that " either the 

 Durchmusterung contains many stars (more than one third 

 of the entire number) which, though rated as 9.5 magnitude, 

 are sensibly below it, or else it must be assumed that at the 

 average distance for stars of this magnitude a denser stratum 

 actually exists, succeeded possibly by regions less fruitful 

 beyond." 



NEW STARS. 



"Schmidt's observations of the new star of 1866 (TCoro- 

 nce), continued up to the present time, show that after fall- 

 ing from the second to the seventh magnitude in nine days, 

 its light diminished very gradually year after year down 

 to nearly the tenth magnitude, at which it has remained 

 pretty constant for the last two years. But during the whole 

 period there have been fluctuations of brightness at tolerably 

 regular intervals of ninety-four days, though of successively 

 decreasing extent. After the first sudden fall, there seems to 

 have been an increase of brilliancy which brought the star 

 above the seventh magnitude again, in October, 1866, an in- 

 crease of a full magnitude; but since that time the changes 

 have been much smaller, and are now but little more than a 

 tenth of a magnitude. The color of the star has shown no 

 change from pale yellow throughout the whole course of ob- 

 servations." 



Lord Lindsay makes the important announcement that 

 Schmidt's Nova Cygni (R. A. 21 h 36 m 52 8 ,Dec.-f 41 16' 53"), 

 which blazed forth suddenly last November, exhibiting a 

 continuous spectrum with numerous bright lines, now gives 

 monochromatic light, the spectrum consisting of a single 

 bright line, corresponding in position to the characteristic 

 line of gaseous nebulae. From this fact Lord Lindsay infers 

 that this star, which has now fallen to 10.5 magnitude, has 

 actually become a planetary nebula, affording an instance 

 of a remarkable reversal of the process imagined by Laplace 

 in his nebular theory. 



