Neighlourhood of the Giant* s Causeway, &c, 377 



Garron point and its neighbourhood, whose rectilineal 

 course is directed towards that part of the Scotch coast. 



The dykes about Larne may be expected to be found on 

 the Mull of Galloway, while those I examined far up in 

 Belfast lough, on account of their S. E. dnection, probably 

 do not catch Scotland, nor meet land until they arrive on 

 the coast of Cuniberland. 



Whether our whynn dykes be identically the same with 

 those on the Scotch coast opposite, is not easily ascertained, 

 though highly pn^bable ; but even C()nl]niag ourselves to 

 our own country, we Hud sufficient matter for astonish- 

 ment in conteu^plating our basaltic area, formed by accu- 

 mulations of horizontal strata, with numberless vertical 

 planes radiating from it : had Dr. Beddoes been acquainted 

 with this structure of our basaltic country, I think he 

 would scarcely have asserted, that *' a right knowledge of 

 basaltcs is conducting us fast to a just theory of the earth." 

 1 think very difl'ttrcntTy Irom Dr. Bcddocs, and conceive that 

 instead of assisting^ basaltic facts are throwing new diffi- 

 culties in the way of cosmogonists, who flatter themselves 

 they have developed the secret of nature; and that those in 

 my country, (to which I confine myself) are utterly irre- 

 (9ancileable to any theory I have met with. 



Two sects of naturalists, distinguished by the names of 

 Volcamits and Plutonists^ have of late taken possession of 

 all the basalt in the world, and have divided it between 

 themselves, under the descriptions of en/pted and uneriipied 

 lava 'j and they have so convinced Dr. Beddoes of the vali- 

 diiy of their cuiim, that he says, *' I shall assume the origin 

 of basahes from subterranean fusion to be thoroughly esta- 

 blished." 



After such a round assumption it may be deemed uncivil 

 to question the igneous origin of our basalt dykes ; but 

 natural history is not to be sacrificed out of respect to con- 

 fident assertion : 1 will therefore try by the test oi Jacts 

 whether that description of basahes (which your lordship 

 wishes for information upon) ever was in fusion. 



Foreigners seem to know little of whynn dykes except in 

 mines. Mr. St. Fond found at Chamarelle in Vivarci^ 

 what is obviously a whynn dyke, and it embarrassed hini 

 more than any fact he ever met wiiii ; it will be found en- 

 tertaining to look into his Vol. ex, de Vivarois, and into 

 h\fi M in. des Vol, to sec. the difficulties into which this 

 cow ant de lave compact e, this ruisseau de lasalie en fusion 

 has thrown him, and the swingeing postulates he is obliged 

 to make, in order to get over them. 



Dr. Hamil- 



