Lunar Occultations for July. 



483 



CORRECTION IN MR. ENYS S PAPER ON THE GRANITE OF 

 PENRYN. 



To the Editors of the Phil. Mag. and Journal of Science. 



Gentlemen, 



A mistake has been committed in the amount of power required 

 in «< cleaving," in my paper on the Granite of Penryn, page 324 of 

 your last Number. 



The account should stand as follows : 



Inches. Inches. Sq. In. 



i 24 by 26 = 624 



Power. 



. 3 3 Wedges. 



Capping 



Quartering 24 by 15 = 360 . . . . 5 jj ^j^ 8 ' 



I may add that some cleavers said that the relative power was as 

 2, 3, and 10. But one of the best informed, who had the most ge- 

 neral acquaintance with the different rocks, though he allowed such 

 might be the fact in some tough rocks, thought that 2, 3, 5 was 

 the average power required, as stated in page 323. 



1 am, Gentlemen, your obedient Servant, 



Enys, May 3, 1833. John S. Enys. 



TEMPERATURE AND HUMIDITY IN FEBRUARY AND MARCH. 



On looking over my former Journals, it appears that the February 

 of this year was the mildest, and also that in which we have had 

 the greatest quantity of wet, of any February these seven years, at 

 least ; and that the succeeding March was the coldest we have had 

 during the same period. Samuel Veall. 



Boston, April 8, 1833. 



LUNAR OCCULTATIONS FOR JULY AND AUGUST. 



Occultations of fixed Stars by the Moon, visible at Greenwich in the 

 Year 1833. Computed by Thomas Maclear, Esq.; and circu- 

 lated by the Astronomical Sociefu. 



3Q2 



