By William Long, Esq. 71 



bis examination of the specimens sent to him of Stonehenge stones 

 is as follows : — 



" Oxford, 22nd December, 1858. 

 Mr Deae Sie, 



" The stones, four in number, are thus to be described: — 



" 1. Marked Stonehenge altar. This is a gray sandstone, composed of quartz 

 sand, silvery mica, and some small dark grains (possibly hornblende). Such a 

 stone might be obtained in the gray Devonian or gray Cambrian rocks — and ia 

 other situations (' Cos.' antiq). 



" 2. Greenstone (Anglice). Composed of slightly quartzose Felspar — horn- 

 blende — a little chlorite ? &c., &c. This is an ordinary greenstone of such large 

 grain and such, a constitution as to make approach to the green syenite of some 

 writers. If I had better specimens I could perhaps determine the presence of 

 other minerals. Such a rock may _be found in dykes in Devonshire, in dykes 

 and seaming beds in Wales, &c. 



" 3. Smaller specimen, like the last, but with finer grain. 



"4. Compact felspar of Mac Culloch: shows no internal crystallization; 

 base of many dark porphyries — such occur in North Wales, Cumberland, &c. 

 If on the spot, we were to study more carefully the several stones, it might, I 

 think, be possible to identify the greenstones ; but by such little atoms as these 

 only guesses and those very vague can be justified. 



" There is nothing like granite in the specimens. This rather points to 

 Wales than to Cornwall — nor is there any ordinary (felspathic) elvan as in 

 Cornwall, but 'Elvan' is a name applied to greenstone dykes not unlike this 

 stone near Dartmoor. But as, no doubt, Merlin brought the stones he might 

 choose a rock now buried in the great depression of Caernarvonshire, where 

 Sara Badrig alone remains to mark his tram-road ! 



But upon this subject, there is no one who deserves a hearings and 

 a more attentive hearing, too, than Mr. Cunnington, F.G.S., who 

 has devoted so much time and thought to the study of the geological 

 character of the Wiltshire megalithic structures. He says, in a 

 paper " on the geology of Stonehenge," read at the Salisbury 

 meeting of the Wilts Archaeological Society, 1865 : " We are in- 

 debted to Mr. Prestwich, the treasurer of the Geological Society, 

 for the exact determination of the stratum from which the 'Sarsens' 

 are derived (Vide Journal of the Geological Society). 



" At the close of the secondary period of geologists, when the 

 Chalk stratum, now forming the downs over which we shall walk 

 to-morrow, was at the bottom of the sea, beds of sands, clays, and 



