66 Dr. Beddoes’s Obfervations on the 
but a little more lifting force to form continued ranges of 
mountains* The road from Welfhpool to Birmingham, above 
threefcore miles, is repaired in a great meafure with whin- 
ftone. A colonnade of bafaltes has been lately expofed in 
digging the Shropfhire canal ; and in the mining country 
around, levels have been driven in the black rock, as it is 
fometimes called. As I have feen whinftone and {late in vari- 
ous other parts of North and South Wales, the whole weftcrn 
fide of our ifland has probably been raifed by the bafaltes on 
which the fuperficial ftrata now reft, though from particular 
circumftances the fufed mafs has now and then cryftallized 
into granite; and as it has been conjectured, that the bafaltes 
of Ireland once joined that of the Scotch ifles and the main 
land itfelf, fo perhaps the bafaltes of North Wales joined the 
Irifh coaft till the fea worked its way or broke in, and de- 
ftroyed the continuation. 
As limeftone is fometimes faid to reft immediately on gra- 
nite fo at the foot of the Wrekin, and at Lilleftiall Hill, 
no (late is interpofed between the limeftone and bafaltes ; fo 
that the analogy extends even to the exceptions. 
But another feries has been obferved, which feems to con- 
nect granite by a clofer tie with the operations of fubterraneous 
fire. In Italy lava ftands to flate and limeftone in the fame 
relation as granite and whinftone in other countries -f • Whole 
ridges of mountains in the Venetian territory confift of folid 
lava, fometimes almoft bare, fometimes retaining the fuper- 
incumbent ftrata, with feveral local variations ; all of which 
are reducible to a greater or lefs degree of lifting force. Thefe 
* Born’s Letters, p. 207. 
t Berber, /. e. pp. 42. 51. ; and efpecially Strange, /. c. p. 24 — 32. 
chains 
