W H I 



fage ; in the fouth he continues the whole year. Ray and 

 Pennant. 



WHINE, a hunting term, ufed in refpea of the cry of 

 an otter. 



WHINEBACH, in Geography, a town of Africa, on 

 the Gold Coaft. N. lat. 5° 30'. W. long, i" 30'. 



WHIN-STONE, in Geology, the provincial name given, 

 in many parts of England and Scotland, to bafaltic rocks : it 

 is alfo applied by miners to defignate every kind of dark- 

 Coloured and hard unilratified rock, which refills the point of 

 the pick. Many geologifls in this country clafs all bafaltic 

 or trap rocks under the term whin-ftone. See Trap. 



The fubftance which fills very large mineral veins is gene- 

 rally dark bafalt, or green-ftone ; hence thefe veins are moft 

 frequently called whin-dykes. Thefe veins being harder 

 than moil of the rocks which they interfedl, remain when 

 the furface on each fide of them is wafhed away, forming 

 enormous walls extending into the fea, or rifing above the 

 level of the country in various parts of their courfe, and may 

 often be traced for many leagues. They occur in the 

 counties of Northumberland and Durham, and on the coafts 

 of Scotland ; and when broken down, they form reefs of rock 

 or iflands. The Earn iflands, off the coaft of Northumber- 

 land, are parts of a bafaltic dyke. When whin-dykes crofs 

 rivers, they form ledges of rock conftituting fords ; or, if 

 very abrupt) they hold up the water on one fide and form 

 cafcades. The Cleveland bafalt, or whin-dyke, defcribed in 

 Mr. Bakewell's Introduftion to Geology, (fee Veins, 

 Mineral, ) has been traced from the coaft of Yorkfhire fe- 

 venty miles into the weftern part of Durham. 



Under the article Mineral Vmss, we have obferved, that 

 when whin-dykes interfeft coal ftrata, they produce a change 

 in the fubftance of the coal, and alfo of the other ftrata, fimi- 

 lar to what might have been expefted from a ftream of 

 melted lava ; and we have recently obferved a fimilar effeft 

 produced on primitive rocks of gneifs,in the vicinity of Aber- 

 deen, by contaft with a powerful whin-dyke. The whin- 

 ftone is alfo changed near its contaft with the gneifs into a 

 reddifh horn-ftone. In other parts, it is a dark granular 

 bafalt or green-ftone. The gneifs has loft its charadlcriftic 

 ftrufture, and becomes porphyritic when near the whin- 

 dyke. Between whin-dykes and the rocks which they inter- 

 feft, there is fometimes a feam of foft argillaceous earth in- 

 terpofed, which is wafhed out when they are near the fea- 

 co^ft, leaving the whin-ftone like a wall placed between 

 two perpendicular precipices. Sometimes the internal part 

 of a whin-dyke will be compofed of foft iron-clay ; in other 

 inftances, tlie dyke will be compofed of folid blocks or prifms 

 of bafalt feparated by fimilar clay. In fome whin-dykes, 

 the fubftance which fills them appears a compadl and 

 folid mafs of whin-ftone, which, however, will divide into 

 four, five, or fix-fided prifms, arranged horizontally. 



Thefe are perfeftly fimilar to the perpendicular bafaltic 

 columns in ftrufture, differing only in their pofition. There 

 is a dyke traverfing the bafaltic ftrata of the Giant's Caufe- 

 way, on the coaft of Antrim, in which this pecubarity of 

 ftrufture is remarkably difplayed. It interfefts beds of 

 columnar bafalt, in which the columns are arranged with 

 great regularity, and are perpendicular to the horizon ; but 

 the whole dyke is compofed of fmall prifms of bafalt placed 

 horizontally, or at right angles with the former. Some of 

 thefe prifms do not exceed an inch in diameter, others are 

 much larger : nthey are for the moft part extremely regular, 

 and are articulated or jointed. 



It has been fuppofed with much probability, that the dif- 

 ferent arrangement of the columnar ftrufture in the beds 

 and in the dyke, is to be attributed to the different circum- 



W H I 



ftances under which they were folidified. If the beds have 

 once flowed as lava under the furface of the ocean, the ba- 

 falt would begin to cool and cryftallize from the upper and 

 lower furface. That this has probably been the cafe may 

 be inferred from thefe beds refting on ftrata that contain 

 marine organic remains, and which mull, therefore, have been 

 formed under the bed of the ocean. 



The perpendicular dykes interfefting rocks already formed 

 would begin to cool from the fides with which they were in 

 contaft, and the procefs would proceed laterally. 



In fome inftances, we find whin-dykes principally com- 

 pofed of globular maffes of ftone feparated by a large quan- 

 tity of foft clay, and the globular maffes are incrufted with 

 ochreous clay : probably the whole of the clay in fuch dykes 

 has been formed from the decompofition of the bafaltic 

 maffes by the aftion of water percolating them. 



Whin-ftone dykes prefent fo many analogies with volcanic 

 rocks in their compofition, and the efFefts which they pro- 

 duce on the ftrata that they pafs through, that we are led 

 to refer their origin to the aftion of fubterranean fire crack- 

 ing the upper rocks and ftrata, and forcing the melted matter 

 into the rent. Under tlie article Volcano, we have ftated 

 many Inftances of vaft rents made in the earth, and filled by 

 eruptions of lava ; thefe rents fo filled with lava may be 

 confidered as whin-dykes of recent formation. This is fur- 

 ther confirmed by the obfervations of M. Cordier, ( fee Vol- 

 canic ProduHs, ) who has fhewn that the fubftance which 

 fills both are effentially the fame, being principally com- 

 pofed of felfpar and augite, with iron-fand and olivine. 

 Whin-ftone not only occupies the cavities of perpendicular 

 dykes ; but it appears to have been, in many inftances, 

 found laterally between the regular ftrata, producing An- 

 gular contortions and diflocations, and almoft always effeft- 

 ing a change in the fubftance of the rock with which it 

 comes in contaft. Sometimes it produces a change in the 

 form of the bed or ftratum which it has paifed through, 

 breaking it into diftinft mafles, or bending it in different 

 direftions, or enveloping large parts of it in the bafalt or 

 whin-ftone. Of this a remarkable inftance is defcribed in 

 the third volume of the Tranfaftions of the Geological So- 

 ciety, occurring on the north coaft of Ireland, in the county 

 of Antrim. (See Plate IV. J!g. i^.. Geology.) a a a reprefents 

 a bed of chalk Angularly bent, and completely enveloped in the 

 bafalt which forms a part of the bafaltic range extending 

 from the Giant's Cauieway. 



The beds of chalk and the other ftrata on this coaft are 

 frequently interfefted by whin-dykes, and a moft remark- 

 able change is obferved in the ftrufture of the chalk in the 

 vicinity of thefe dykes. In immediate contaft with the 

 whin-ftone, and to a confiderable diftance on each fide, the 

 chalk is converted into marble, having the granular texture 

 of primitive lime-ftone, or what the French call calcaire fac- 

 caroide, from its refemblance to the grain of loaf-fugar, ( fee 

 Plate IV . Jig. 5. Geology,) which reprefents two adjoining 

 whin-dykes ab, interfefting the chalk c <: c ; the dyke a is 

 thirty feet in width, the dyke b twenty feet, and the inter- 

 vening mafs of chalk twenty feet. The mafs of chalk be- 

 tween the two large dykes is interfefted in a zigzag direc- 

 tion by a fmaller dyke. To a certain diftance from the 

 whin-ftone, the chalk is perfeftly cryftalline, but it gradu- 

 ally approaches to the charafter of the chalk at a greater 

 diftance from the dyke. In various parts of the world we 

 obferve trap or whin-ftone occurring in apparently regular 

 beds, either covering ftratified rocks, or interpofed between 

 them ; fuch have been called by the Wernerian geologifts 

 floetz trap-rocks, and their occurrence in this pofition has 

 been urged as an argument for the aqueous formation of 



fuch 



