IBS 



Not ices of Books : 



[July 



with the Rev. Dr. Biyce, supposes it to be composed of sienite and 

 granite, and in some parts of a grey rock much divi&led by veins of 

 quartz, and in other i^laces a black rock capable of being highly polish- 

 ed prevails. 



" The AravulJy range extends from Mount Abu to the north-east 

 progressively diminishing in aljitude to Delhi, where rocky protrusi- 

 ons disappear. Near Hansi, however, in 29^ N. lat. and 76^ E. long, 

 the hill of Tooham, a bold granitic mass, according to Mr. Fraser 

 about 700 feet high though surrounded almost by plains, is sufficiently 

 connected by low rocky ridges with the Aravully to justify its being 

 considered as the extreme termination of the chain in this direction.* 

 It is only under the 73^ and 74*^ E. long, that this chain attains the 

 elevation of 3500 feet, the summits rising however on the side of Cen- 

 tral India form a platform two thousand feet high. 



" We are not aware that Barometrical measurements have been made 

 on the opposite side of the range, but from the Alpine character the 

 peaks of the Aravully are said by Colonel Tod to assume when viewed 

 from the desert, it would seem that the difference of level between the 

 northern, compared with the southern foot of this chain must be very 

 considerable. 



" According to Colonel Tod the Aravully range is composed of gra- 

 nite reposing on a dark blue slate, the latter rarely appearing much 

 above the base of the superimposed granite. The internal valleys 

 abound in variegated slate, gneiss and sienite appear in the intervals, 

 and the diverging ridges of Ajmere and the Chittore range are com- 

 posed of quartz. 



" The Aravully from Delhi to Abu, and the continuous hills forming 

 the entire northern and western boundary of the general plateau of 

 Central India, have been considered to belong to what geologists have 

 named primary rocks, but a careful examination of what has been 

 written regarding the structure of this extensive tract is sufficient to 

 satisfy the most scrupulous mind that these formations are i<ientical in 



tc * If -^ve consider the direction of mountain chains as marking the course in which the 

 moving forces by which they were raised extended, we shall find the Sivalik hills, recently 

 tendered so celebrated by their imbedded fossils, will come within the Aravully zone, as 

 the Kasya mountains have been brought within that of the Vindhya. It is also worthy of 

 remark that the several ruined cities, which according to tradition have been destroyed by 

 earthquakes and other volcanic causes, are found chiefly v. ithin these bands. The subter- 

 ranean town discovered 23 feet beneath the alluvium of the Doab near Behut by Captain 

 Cautley, containing Indo-Scythic coins referred by Mr. J. Prinsep, {Jour. Asiat. Sgc» 

 1834, p. 43,) to the commencement of the Christian era, can hardly be accounted for other- 

 wise than by the subsidence of the site on which it stood." 



