168 Miscellaneous Intelligence. 



tion, he remarked very unequivocal traces of polarization hy re- 

 fraction in the light of which the halo was formed. This experi- 

 ment excludes all explications of the phenomenon founded upon 

 the hypothesis of a reflexion. M. Arago thinks that the instru- 

 ment he made use of in this observation will enable him more ge- 

 nerally to ascertain when a cloud is frozen, and that it will then 

 supply the means of studying the law of the diminution of heat in 

 the atmosphere. — Ann. de Chimie, xxix. 77. 



7. Nature of Shooting Stars seen during Day-Time. — An account 

 Iby Professor Hanstein of a shooting-star seen in the day-time, has 

 recently attracted some little attention*. Mr. Dick, however, 

 doubts the assigned nature of the appearances, and states reasons 

 for concluding it to be nothing more than a bird. Whilst making 

 observations twelve years ago on Venus, when close to the sun, 

 he, whilst looking for the planet, remarked a body passing across 

 the field of the telescope, apparently of the size of Venus, but 

 varying a little in this respect ; at first it was mistaken for the 

 planet, but its rapid motion corrected the error. In some instances 

 four or five of these bodies appeared to cross the field of view, 

 sometimes in a perpendicular, and at other times in a horizontal 

 direction. They appeared to be luminous bodies somewhat re- 

 sembling the appearance of a planet, when viewed in the day- 

 time with a telescope of moderate power. Their motion was rapid, 

 and inclined to a waving or serpentine form. After twelve months' 

 observation, Mr. Dick was enabled, by observation of some which 

 were larger than others, to decide they were birds, whose bodies, 

 illuminated by the solar rays, reflected light enough to produce 

 the appearance. In a hot summer's day, when a similar pheno- 

 menon has been observed, there was every reason to attribute it 

 to a number of winged instruments flying at no great distance 

 from the telescope. 



Mr. Pick observes that Professor Hanstein's account of the kind 

 of motion as being unequal, and resembling that of a rocket, cor- 

 responds to the motion of birds through the air. He remarks too, 

 that an appearance observed by the late Mr. B. Martin, of certain 

 bright round bodies running towards the sun, when viewed in 

 particular circumstances, may be explained in the same manner. — 

 Edin. Phil. Journal, xiii. 167. 



8. Astronomical Prize Question. — " Method of calculating per- 

 turbations of the elliptical motion of comets, applied to the deter- 

 mination of the approaching return of the comet of 1759, and to 

 the motion of that observed in 1805, 1819, and 1822." The prize 

 a gold medal of 3000 francs value. Memoires received till Jan. 1, 

 1826, — Royal Academy of Sciences, Paris. 



* Quarterly Journal, Vol. xix. p. 369, 



