PROCEEDINGS 



THE GEOLOGICAL SOCIETY OF LONDON. 



Vol. IV. Part IL 1844. No. 101. 



Februakt 21, 1844. 



The following commtinications were read : — 



1. Some Remarks on the White Lemestone of Corfu and ViDO. 

 By Captain Portlock, R.E., F.G.S. 



As I have reason to expect that I shaU hereafter be able to pre- 

 pare a detailed account of the Geology of the Ionian Islands, and 

 have at present but few data for a description of even the Kmited 

 portion of the country as yet examined, I now only offer a few 

 remarks on that portion of the white Hmestone which is adjacent 

 to the city of Corfu, and occupies the whole of the Island of Vido, 

 and on the more recent strata connected with it- 



On approaching Corfu, the physical aspect of the country is very 

 striking. Monte Decca on the south, and San Salvador on the 

 north, the former with its sharp, broken, rugged outline, the latter 

 with its conical peak rising from a long ridge, and both exhibiting 

 steep faces marked by numerous deep furrows, by no means recall 

 the ordinary forms of limestones in our more northern countries ; 

 but the type they present wiU, I think, be found to have a con- 

 siderable geological range. 



In the Venetian harbour of Go vino a singular variety of this 

 limestone may be seen, and is thence traceable in rough knolls 

 running in a westerly direction to the north of the village of P6- 

 tamo. Its dark, rugged, and often ochreous aspect, its sonorous 

 fracture, and its impurities, are strong features of distinction be- 

 tween it and the ordinary white limestone. It is traversed by 

 numerous crystalline veins of a yellow saccharoid carbonate of lime, 

 which I have little doubt is highly dolomitic ; and it is full in- 

 ternally of small bubble-shaped cavities, some of which are empty, 

 and others contain a fine powdei', the nature of which I have not 

 yet determined. I believe this limestone to be of volcanic origin, 

 or at least much changed, although no ordinary volcanic or other 

 igneous rocks have as yet been discovered in the island. 



VOL. rv. PART n. E E 



