1852.] STRICKLAND PSEUDOMORPHOUS CRYSTALS OF SALT. 5 



to be so, the disturbance was felt at Terceira before St. Michael's, 

 and at the latter place before Fayal ; and the progress of the move- 

 ment was slower than wonld be expected. 



To judge by the effects, the explosion would appear to have taken 

 place at a short distance from the west end of St. Michael's ; the 

 force of the shock at Angra, at a distance of ninety miles from that 

 end, having been the same as at Villa Franca, a town of St. Michael's, 

 thirty miles in the opposite direction ; and the greatest damage at 

 St. Michael's having occurred in the north-western parts of this 

 island. 



I may add, without reference to any hypothetical reasoning, that 

 the fall of rain in March was nearly three times the average of this 

 usually rainy month, and that an average month's rain fell between 

 the 17th and 21st of April. 



British Consulate, St. Micliael's, 

 June 30, 1852. 



2. On the Geology o/^ South Africa. By G. A. Bain, Esq. 



[Communicated by the President.] 

 [The publication of this paper is deferred.] 



December 1, 1852. 



John Moxon Clabon, Esq., James P. Eraser, Esq., The Rev. Os- 

 mond Fisher, Sir Charles Fellows, Professor Frederick M'Coy, and 

 Edward Wood, Esq., were elected Fellows. 



The following communications vrere read : — 



1. On PSEUDOMORPHOTJS CRYSTALS of ChLORIDE of SoDIUM ill 



Keuper Sandstone. By H. E. Strickland, Esq., F.R.S., 

 F.G.S. 



About one-third of a mile S.S.W. of the village of Blaisdon in 

 Gloucestershire, I lately noticed in the side of a road some thin 

 flaggy beds of the peculiar white sandstones, alternating with green- 

 ish marl, which have long been recognized in this country as the 

 equivalents of the Keuper Sandstone of Germany. At this locality 

 they are elevated at the unusually high angle of about 45°, dipping 

 to the E. by S., a position which they doubtless owe to their proxi- 

 mity to the elevated Silurian mass of Blaisdon and Huntley Hills, 

 distant only a few hundred yards on the W., and connected north- 

 wards with the May Hill range. For though the chief elevation of 

 those Silurian rocks doubtless took place prior to the deposition of 

 the Triassic series, yet there are abundant proofs along the E. flanks 

 of the May Hill and Malvern ranges that additional upheavals were 

 communicated to those masses subsequently to the Triassic period. 



These beds of Keuper Sandstone thus elevated, are ripple-marked 

 on their surface, and present the usual characters of the stratum as 



