[ 261 ] 



XXXI. On the Crystalline Form of Pyrosmalite: hitherto 

 undescribed. By H.J. Brooke, Esq., F.R.S., fyc* 



1LTAVING in my possession a specimen of this mineral 

 -*--"- with well-formed crystals resembling the annexed figure, 

 and having measured them with the reflective goniometer, I 

 am enabled to supply a description of their form, which has 

 not yet, that I am aware of, been given. 



Assuming, for the sake of simplicity, the regular hexagonal 

 prism as the primary form, and that the 

 planes b result from a decrement by one 



row corresponding to B, the ratio of a 

 terminal eilge to a lateral edge will be 

 found as 15 to 16 nearly, and the planes 



a will correspond to the symbol B. 



The angular measurements are as fol- 

 lows: 



Pon a = 148° 30' 

 b as 129 13 

 M m 90 

 MonM' = 120 H.J. B. 



XXXII. Papers on the alleged Periodical Meteors of the 1 3th 

 of November, and on Shooting Stars in general. By M.M. 

 Wartmann and Quetelet. 



I. Notice respecting the Periodic Meteors of the 1 31 h of 

 November. By M. L. F. Wartmann f. 



A COSMOLOGICAL phenomenon of the most interest- 

 -£** ing kind, although new as yet in the records of science, 

 is at present attracting the attention of astronomers, meteor- 

 ologists, and physicists. The magnificent assemblage of lumi- 

 nous points and globes which has been seen for several years 

 presents a highly important subject of inquiry, by which we 

 may be enabled to add to the stock of our knowledge respect- 

 ing the constitution of our planetary system. 



The appeal made upon this occasion by M. Arago spread 

 far and wide, and this very year [1836] numerous observations, 

 made in different places, have been sent to the illustrious philo- 

 sopher who had asked for them. They concur in showing that, 

 towards a point of the heavens at a small distance from the 

 stars /3 and y in the constellation Leo, a considerable quantity 

 of shooting stars seem to be produced, and to succeed one 



* Communicated by the Author. 



t From the Bibliotheque Univcrsclle, N. S. 2 de Ann. No. 18, June 1837: 

 having been read before the Society of Physics and Natural History of 

 Geneva, Dec. 15, 1830. 



