S30 ANNUAL OF SCIENTIFIC DISCO VERY. 



Our readers will bear in mind that the condition of these meteors is 

 not one of incandescence, or ignition, while traversing space beyond 

 the limits of our atmosphere ; and it has often been wished that we 

 might be favored with some observations of them while in the course 

 of their interplanetary progress. This opportunity has been given 

 within the last year to M. Hois, a European astronomer. At 8h. 

 81m. P. M. on the 4th of October last, as he was observing the milky 

 way, he distinctly saw a dark mass slowly wending its way along the 

 half-illumined sky, eclipsing the stars in its path. He was enabled to 

 watch this strange visitant from a point situated in a 280 ^-j- 21 to a 

 291 -f- 18, where it finally disappeared. How fortunate it would have 

 been for us if another observer, as skilled as M. Heis, had also been 

 favored with a sight of this dimmest of planets ! 



Prof. Newton, in a recent communication to Silliman's Journal, 

 after assigning a period of about 38 years for the recurrence of the so- 

 called " meteoric showers," thus speculates in regard to the next prob- 

 able great display : If a shower occurs in 186o (32 years after the 

 great November display of 1833), it seems most reasonable to look 

 for the linest appearance "in western Asia and eastern Europe; and 

 in 1866 on the western Atlantic. The year in which we have most 

 reason to expect a shower, is 1866, since the cycle of 33'25 years is 

 probably to be reckoned from some date between November in 1832 

 and in 1833. These places and times are named with hesitation, 

 rather to guide observation, than as predictions. The causes alluded 

 to above, and the possible perturbations and irregularities of structure 

 of the group, may cause unexpected variations of time and place." 



STARS THAT HAVE CHANGED THEIR COLORS. 



Some additions to the catalogue of these stars are given by Mr. Jacob 

 Ennis, in the Proceedings of the Academy of Natural Sciences at Phila- 

 delphia, based on the observations of Humboldt, Donati, Herschel, 

 Schmidt, and others, including himself. He says, " among 'the 11 stars 

 of the first magnitude, visible in this latitude, seven, according to these 

 evidences, have undergone changes of color, and some of them more 

 changes than one. Among the six stars of the first magnitude in the 



*j *3? <j 



Southern Hemisphere, not visible here, two have changed their colors. 

 And nearly all these changes have been sudden, transpiring in v ehort 

 periods. Moreover, none of the 11 first magnitude stars visible here 

 are white ; all are either red, yellow, green, or blue. Why has Jt not 

 been made known long ago ? Probably in great part, because changes in 

 the color of stars could not be accounted for by any prevailing scien- 

 tific theory. It has been rationally assumed that the stars are similar 

 in constitution to the sun, and the sun has been encircled with a theory 

 which alfords not the least clue to any changes of color. This theory 

 is most singularly complicated and unfortunate. It surrounds the sun, 

 said to be dark, with an apparatus consisting of five distinct atmos- 

 pheric envelops, all regularly arranged one above the other : First, 

 a transparent envelop touching the opaque body of the sun : secondly, 

 a fiery luminous envelop : thirdly, another transparent envelop : 

 fourthly, another fiery luminous envelop : fifthly, a transparent enve- 

 lop, surrounding all the others. Among such a number of imaginary 

 things, there seems to be no room to imagine how changes of color 



