174 Prof. C. Piazzi Smyth's Astronomical Notices. 



Ferret. By a single direct barometrical comparison with 

 Geneva, I obtained 11,284 English feet above the sea, or 140 

 feet higher than the Col du Geant. I was successful in tra- 

 versing the Glacier of Salena to Orsieres the same day, a pass 

 which has not before been described, and which has this in- 

 terest, in addition to the singular wildness of the scenery, 

 that it includes those regions of beautiful crystallized pro- 

 togine, here in situ, which have been known to geologists 

 hitherto chiefly from the numerous moraines which they 

 form in the valleys of Ferret and of the Rhone, and especi- 

 ally the majority of the blocks of Monthey, which have been 

 derived, according to M. de Buch, entirely from this region 

 of the Alps. I remain, my dear Sir, yours very truly, 



James D. Forbes. 



To Professor Jameson. 



Astronomical Notices, By C PlAZZi Smyth, Esq., F.R.S.E., 

 Professor of Astronomy in the University of Edinburgh. 

 Communicated by the Author.* 



These notices are merely, in general, the contents of such letters as 

 are continually arriving at the Royal Observatory on the Calton Hill, 

 from various members of the large body of correspondents, at home 

 and abroad, which the establishment of such an Institution neces- 

 sarily gives rise to. 



Many communications of much importance are thus received, and 

 it will doubtless be a matter of interest to some members of this 

 Society, as well as of advantage to the authors, to lay the papers on 

 the table for inspection during a few days, merely ^saying a ^evf words 

 in explanation at the present time. 



Some care in selection certainly is necessary ; for when one gen- 

 tleman writes, as he did lately, from the north of Scotland, " that 

 he considers the distance of the earth from the sun is not known, and 

 that it is not understood what keeps the sea within its bounds ; that 

 he will be glad of my opinion thereon, as he intends to bring those 

 matters to a final and satisfactory conclusion;" and when another 

 writes " that a French astronomer has concluded, from his own 

 observations on the moon, that in seven years that body will be in 

 contact with the earth ;" or another, " that he can predict all the 

 changes of the weather by the configurations of the satellites of Jupi- 

 ter ;" when men will write such things, it is sufficient expenditure 



* Read before the Royal Society, Dec. 16, 1850. 



