102 Dr Clwistie on the Meteorology^ Geology, S^c. 



into regular vertical strata. The superficial lamihse havd,' in 

 many places, separated at the seams, and by exposing those be- 

 low, have afforded a proof that the seams extend through the 

 whole mass of the hill. A transverse section of the hill would af- 

 ford an appearance like that represented in Fig. 2. Plate IV. This 

 granite is, in some places, penetrated by small veins of quai-tz, 

 which, on approaching a seam, leave their original direction, 

 follow the course of the seam for a greater or less distance, and 

 again abruptly leave it. 



The two surfaces of the laminae are often perfectly parallel ; 

 and when they are not of a great thickness, they can be very 

 easily raised in slabs of any size, for architectural purposes. It 

 is seldom, however, that they are of precisely the same thick- 

 ness for any great extent ; and sometimes this varies prodi- 

 giously within a very short distance. In some instances of this 

 description, the granite loses its laminar appearance. Thus, 

 when a lamina becomes very rapidly thinner, so that its two 

 surfaces meet, it acquires the shape of an immense wedge, which 

 is not unfrequently met with. In such cases, the term laminar 

 is rather inapplicable. At the same time, it must be remember- 

 ed, that these are extreme instances, which are connected by 

 many intermediate links to the most perfect form of this struc- 

 ture. Although, therefore, we would not apply the term lami- 

 nar to these cases individually, yet it is perfectly evident that it 

 is quite accurate as a general term, applied to the prevailing 

 structure of the granite of India ; and that, when we analyse the 

 various appearances which the granite presents, they may be all 

 considered as varieties and modifications of this structure. 



There are several instances, in the Hydrabad country, of huge 

 natural columns, formed of four or five separate masses of gra- 

 nite, piled with great regularity on each other, with part of their 

 surfaces accurately adapted. These, in some instances, occupy 

 the summits of gentle hills ; and from all the appearances con- 

 nected with them, it is perfectly clear that the different masses 

 continue to occupy their original situations. The following is pro- 

 bably the manner in which this curious appearance has, in many 

 cases, originated. Suppose Fig. 4. Plate IV. to be a hill of larijihar 

 granite, it is evident that if the laminae be liable to be split and 

 disintegrated by the action of the weather, those parts which 



