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carefully considered. The conditions to be fulfilled in 

 the construction of a perfect roadway, are, an easy grade, 

 a well drained and smooth surface, a firm, dry road-bed, 

 and durable materials. The cost will be governed by 

 the character of the materials used, and in this connec- 

 tion it is proper to take into consideration the fact that 

 there is lying upon the surface and distributed through 

 the drift a very large quantity of boulders, chiefly com- 

 posed of Diorite — a species of trap or basaltic rock 

 transported from a distance during the drift period — the 

 time that a greater portion of the soil of Long Island 

 was transported where it now lies. It possesses both 

 hardness and tenacity, essential qualities for a durable 

 road material ; but its excessive hardness renders it 

 difficult to break into small pieces, and therefore perhaps 

 too expensive to be used — much will depend upon the 

 cost of breaking it up. There is also found in the drift 

 a large quantity of other stone, which, though not equal 

 to the former in hardness or tenacity, yet possesses these 

 qualities to a sufficient degree not to warrant their being- 

 rejected as road material. These stones have gone 

 through the same process of attrition which has rounded 

 the edges and smoothed the surfaces of the former, and 

 they were submerged for the same period in that flood 

 of water without disintegration. To the eye, no more 

 effect has been produced on one than on the other. If 

 they have been able thus to withstand the effects of the 

 elements and of attrition, they will answer to a certain 

 extent the purpose for which we require them ; in fact, if 

 there were no harder stone, we should consider this very 

 good material. The same quality of stone to which we 

 have referred, may be obtained already broken into the 



