314 MATHEMATICS AND KATTJHAL PHILOSOPHY. 



MATHEMATICS AND NATURAL 1'HILOSOriIY. 



NEW PLA.HBT. 



A Dew planer, of great brilliancy baa been recently discovered by M. Ohacorni c, 



of the Paris Observat, . 



THK COMET OF 1866. 



M. Rabin et, an eminent French astronomer, and member of the Academy of 

 Sciences, in an article recently published, h i etaile res- 



pecting the comet which is expected to make its appearance about the year 185G : — 

 " This comet is one of the grandest of which historians make mention. It was seen 

 in the years 104, 392, 683, 9*75, 12>4, and the last time in 1666. Astronomers a- 

 greed in predicting its return in 1848, but it failed to appear. Already the obser- 

 vatories began to be alarmed for the fate of the beautiful wandering star. Sir John 

 himself had put a crape upon his telescope, when a learned calculator of Middle- 

 burg, M. Bomme, reassured the astronomical world of the continued existence of 

 the venerable and magnificent comet. Disquieted, as all other astronomers were, 

 by the non-arrival of the comet at the expected time, M. Bon;. pre- 



paratory labors of Mr. Iiind, has revised all the calculations, and estimated all the 

 actions of all the planets upon the comet for three hundred years of revolution, — 

 the result of this patient labor gives the arrival of I »■ ith 



an uncertainty of two years, more or less ; so tbatfrom 1856 to 1 pect 



the great comet which was affirmed to be the cause of Em- 



peror Charles V., in 1550." 



COLORS SEEN THROUGH THK STEREOSCOPE. 



At a recent meeting of the Manchester Photographic 1 an 



interesting paper on the stereoscope and its application tophi:'.' A practical 



discussion followed, in the course of which Mr. Sidenotham drew attention to the 

 results produced by looking at two different colors through the stereoscope. Blue 

 and yellow, he said, produced (to his si ; red and green produced a dirty 



white ; a blue spot and red bars produced purple bars and white ; and the two colors 

 that seemed most readily to combine were blue and red, producing a bright purple. 

 Blue and yellow did not form a goi in the first instance, and required look- 



ing at a short time. — Mr. Dancer said that to some persons' sighta different colours 

 combined more easily than toother persons', to whom each ■ 

 domi itely; and the eye, lie thought required some education, as it was 



only by looking steadily that the colours were re-compos' —In 



one instance, Mr. Sidebotham Stat rs of differei i heck 



of one colour, the other being ent be solution • y, it 



was suggested, might be arrived at by throwing the prismatic colors upon paper; 



AMERICAN TELESCOPE. 



The Telescope recently procured for the Observatory at Ann 

 is the third in size in the world. The object glass is thirteen inches in dian 

 Few persons have a correct idea of the time, the toil and the skill requisite to pre 

 pare one of these glasses. First, there arc the manufactures of the rough disks. 

 A mass of glass weighing about 800 lbs. is melt' When in a state of 



perfect fusion, the furnace is walled up, and the whole is left to cool The 



cooling process occupies some two months. By this process the glass is annealed. 



