176 SUB-HIMALAYAN ROCKS OF N. W. INDIA. [CHAP. VII. 



massive sandstone rocks. Among the older rocks there is no stone 

 fit for anything but that for which rough rubble may be used. There 

 are several examples of native architecture along the border of the 

 plains, for which an excellent building stone was obtained from rocks 

 of the Sivalik group, but it must have been found in detached blocks 

 and discontinuous bands, the mass of the rock being quite unfit for 

 the purpose. Stone fit for ornamental or monumental purposes might 

 be found among the thick-bedded, hard limestones of the Krol group. 



Slates.— The absence of building stone among the rocks of the 

 Himalayan series is in some places atoned for by the existence of a 

 good roofing material. Mention has already been made of this substance 

 at p. 72, in connection with the subject of cleavage. The variety of 

 slate procured along the flanks of the Dhaoladhar, and used at 

 Dalhousie and Dhurmsala, has proved of first rate quality for roofing 

 purposes. Its fissility is all that need be desired ; it dresses easily, 

 and can be procured of ample size. It is a nearly pure siliceous rock r 

 of pale gray colour, and is not so fine in its minute texture as ordinary 

 slate, and is therefore not applicable to some purposes for which the 

 latter is used. The slate so extensively used at Simla is in every way 

 inferior to that of the Dhaoladhar ; it is distinctly a lamination-slate, 

 A material as good as this could, I imagine, be found among the Infra 

 Blini strata almost at any point, unless of course where crushing action 

 had been excessive. 



Lime and Cement Stones. — Here, as in all parts of India, the stone 

 most in favour with the natives for burning into lime is porous tufa. 

 The climatal conditions are peculiarly favourable to its production. It 

 is to be found everywhere along the flanks of the limestone ridges, 

 and in many places, where its existence is not so easily accounted for, 

 on ledges, and in little basins of the Sivalik rocks." In many cases 

 these basins are evidently small dried-up lakes ; they may all have 

 such an origin. Lime is in many places obtained by burning boulders 



