No. 216.] 237 



jectionable for the purpose of pavement, as it is subject to crum- 

 ble, and the gneiss is apt to flake on the edges, and thereby soon 

 shew a round sarface. There are other formations of stone which 

 may be used in the absence of the above nained materials, the dura- 

 bility of which depends as much on the formation, as the composi- 

 tion of this stone is of the most durable nature, and the formation 

 being uniform and compact it is not subject either to crumble or 

 flake on the edge. Our city is highly favored with an abundance of 

 the above species of stone, the trap formation commencing some 

 miles below the city on the western shore of the Hudson, and ex- 

 tending to some thirty miles above, forming what is termed the pal- 

 lisades, from which most of the boulder formation from which our 

 pebble pavements are made, and from which the material of the 

 famous Russ Pavement is procured in the natural prismatic form in 

 the quarry, where they are broken and dressed to the required size, 

 thence they are transported to the city for use. This city is remark- 

 ably well supplied with the other materials required to complete the 

 finishing of a street, such as curb and gutter and flag stone. All of 

 the above materials are furnished from a range of schistus running 

 from the Helderburgh Mountains, in Albany county in this State, in 

 a southwest direction into the interior of the State of Pennsylvania. 

 The size of the curb, as required by our city ordinances, is 20 inches 

 wide, by six inches thick, and in length, of not less than three feet, 

 the gutter stones are required to be fourteen inches by six inches 

 thick, and in length, of not less than three feet square, and the flag 

 stones are from two to six feet square, and from two to three inches 

 thick, and laid at a cost from 10 to 20 cents per superficial foot, 

 curb six to twenty inches at 30 to 35 cents per running foot; pre- 

 paring the road bed, including excavating two feet deep, and filling 

 with sand and gravel one foot deep, at 16 to 18 cents per yard, 

 amounting to about 46 to 50 cents per superficial yard when finish- 

 ed. The probable cost of the dry square block pavement as describ- 

 ed in the accompanying diagram would probably be about $3 per 

 yard, while the cost of that laid by Mr. Russ has been about $5 

 per superficial yard, when finished complete as described in the ar- 

 ticle above referred to. A copy of the Annual Report of the Ameri- 

 can Institute, made to the Legislature April 20, 1847, will accom- 

 pany this communication. 



