366 Scientific Intelligence. — Mineralogy. 



mlna, while, on the other hand, he shewed that all the lamina? 

 parallel to the axis do not possess the same properties with rela- 

 tion to sonorous vibrations, although they appear to act simi- 

 larly with relation to light. — Memoir read to the French Aca- 

 deme/, — not published. 



14. Glassy Felspar, now called Ryakolite. — It results from 

 some late measurements of G. Rose, in Poggendorf 's Annals, 

 that the angles of this mineral are different from those of adu- 

 laria and the other species of felspar ; that the specific gravity is 

 2.576, and its optical proportion different from those observed 

 in adularia. This mineral occurs, as is well known, in Vesu- 

 vius, and in the lava of the Lacher Lake, &c., — hence, from 

 its occurrence in lava, Rose names it Ryakalite, from gu«| lava, 

 and A<^-«5 stem. 



15. Discovery of Iodine and Bromine in certain salt-springs 

 and mineral waters in England. — Dr Daubeny, in the number 

 of the Annals of Philosophy for September 1829, announces, 

 that he has found bromine in a separate state in the Chesliire 

 salt-springs, and also iodine in two or three of them. He has 

 also detected iodine in the springs of Cheltenham, Leamington, 

 Gloucester, and Tewkesbury. 



16, Examination of a Limestone Deposiie, by M. Vauquelin. 



In digging the foundations of a spinning establishment, in 



the parish of St Maclou, arrondissement de Pont-Audemer, de- 

 partment of the Eure, there was found a large deposite of lime- 

 stone, having a porous texture, and presenting in some of its 

 parts ramifications in the form of stalactites, more than a foot 

 long, and of different diameters, hollow in the centre, and closed 

 at one of their extremities. The colour of these stones is yel- 

 lowish internally, and of a shining brown externally, like cer- 

 tain varieties of manganese. M. Vauquelin, on analyzing them, 

 found products which satisfied him that this substance contain- 

 ed a great quantity of animal matter. The stalactites and 

 other rudiments of crystallization which it presents, induce the 

 author to suppose that it has been dissolved in water with the 

 aid of carbonic acid. But what appears to him remarkable is, 

 that the organic substance could have been preserved so long. 



