Mr. Movie on the Atmosphere of the Cornish Mines. 357 



evident, would not apply to the hypothesis I have ventured 

 to adduce ; and, indeed, if these meteors might be regarded 

 as owing their origin to energetic electric currents, it would 

 not be difficult to assign a supposititious reason for the gene- 

 ral, although not invariable direction of these meteors con- 

 trary to the motion of the earth in its orbit, and also for their 

 greater frequency in tropical regions. This, however, would 

 embrace too wide a field to enter upon at present. 



Since the former part of this paper was written, M. Quete- 

 let's memoir, containing his Catalogue des Principals Appa- 

 ritions des Etoiles flantes (which I had not previously seen), 

 has been placed in my hands. From this it appears, that 

 M. Quetelet, as well as other distinguished observers, concur 

 with me in the opinion that the periodical shooting stars are 

 connected with other meteorological phaenomena. I also per- 

 ceive that M. Quetelet cites some of the same instances ad- 

 duced by me in support of this assumption. The additional 

 facts given in my paper may, however, prove both interesting 

 and confirmatory. 



In addition to the periodical appearance of these meteoric 

 phaenomena on the 12th of November and the 10th of August, 

 M. Quetelet has pointed out other epochs when similar me- 

 teoric phaenomena have been observed, recurring with appa- 

 rent periodicity. The epochs thus indicated are the 2nd of 

 January; the 23rd or 24th of April ; from the 15th to the 20th 

 of June; the 18th of October; and the 6th or 7th of Decem- 

 ber. The increased number of the apparently periodical me- 

 teoric phasnomena perhaps adds to the difficulties attending 

 the hypothesis of a zone or zones intersecting the ecliptic. To 

 a hypothesis attributing their origin to electric currents, the 

 more frequent recurrence of such phaenomena offers no dif- 

 ficulty whatever: for, if electric currents be occasionally thus 

 energetically developed, there appears no reason to infer that 

 this phaenomenon may not repeatedly occur, whether periodi- 

 cally or otherwise, and not be restricted to one or two annual 

 displays. 



October 6, 184]. R. M. Z. 



L. An Analysis of the Atmosphere of some of the Cornish Mines. 



By M. P. Moyle, Esq * 



A PREMIUM having been offered for " the best analysis 



***- of the air taken at the termination of a core of two men, 



from the extremity of one mine level in granite, and of another 



in killas ; the samples to be as fairly taken as possible, and in 



* Communicated by the Author. 



