Description of the New-York Croton Aqueduct: In English, German and French

Couverture
The author, 1846 - 62 pages
 

Autres éditions - Tout afficher

Fréquemment cités

Page 21 - D, of 12-inch hemlock timber, successively built up ; the walls were connected by ties, and filled with stone closely packed in ; the top was covered with 6-inch plank of white pine, and treenailed ; upon this planking the timber-piers f and G were erected, but only .F covered with plank. While erecting those piers, the space E was filled with concrete, and the piers near the top connected with ties. Both these piers, together with their filling of concrete, being the armature of the dam, served...
Page 27 - The sand for concrete, containing coarse and fine grams, was first mixed with water, then there was added to it from 2 to 2^ broken stone of the size of li inch, or the same amount of coarse gravel, and worked till the mass became uniform, and the broken stone completely covered and bedded in the mortar. Immediately after this preparation the concrete was laid and settled with a stamper, till the surface had the appearance of an even floor. The courses were laid not over 6 inches thick. For brick...
Page 22 - H-inch locust (robinia pseudo acacia) treenails of 13 inches in length. Against the rear of this timber pier the one marked L was erected; against the back-water only, it has a regular timber wall, Fig.
Page 24 - ... erected of round timber, filled up with dry stone. The object of this secondary dam is to divide the head of water, and, by means of the water-basin formed by it, to break the body of water running over the weir, and to keep the wood-work of the timber piers K and L under water.
Page 24 - Figs. 288 and 289, is constructed ; it ia erected of round timber, filled up with dry stone. The object of this secondary dam is to divide the head of water, and, by means of the water-basin formed by it, to break the body of water running over the weir, and to keep the wood-work of the timber piers K and L under water.
Page 21 - Fig. 61, occasion for which was given by the rock lying here affording a good foundation : the remainder of the river profile to d, was to be filled with an earth embankment A considerable freshet, however, carried away this embankment wheu partly completed, and it was resolved to extend the stone dam 180 feet further, to c.
Page 48 - ... of the river, across it, resting on the coffer-dams which were placed round each pier, and up the opposite side to the aqueduct again, through which the water was conveyed until the completion of the bridge. In order to keep the air, which is confined in the closed aqueduct, in communication with the atmosphere, there are 33 ventilators, erected for this, purpose, which are placed at the distance of one mile from each other. Every third one is larger than the others, and has a door by which the...
Page 36 - The bank of the island, being of solid gneiss-rock, rises with a slope of 35 ° to the height of the top of the aqueduct. The slope of this rock below water, as far as it could be examined, is steeper, and disappears under a deposit of mud mixed with sand and bowlders. It is supposed this rock has connection with that of the opposite shore. In the basin formed by its depression below the strait is deposited a mass of white marble, upon which the gneiss and alluvium of sand, mixed with pieces of rock...
Page 29 - Fig. 20S, the channel of the aqueduct is widened, and the water runs through an arch in the bulkhead aa, then passes the screen-frame, a set of guard-gates, and a set of regulating-gates. The screen, formed of oak slabs 6 inches by 1, allowed a quantity of fish to pass through the 1-inch spaces into the aqueduct. In order to prevent this, a fine brass netting was put over the screen, through which only very small fish could pass ; to prevent which, other artificial preparations will be required....
Page 27 - Etone was to be had near, the side-walls could be carried up ; also the roofing-arch, which in this case was turned 12 inches thick ; this, however, has been carried into execution in but few instances. The courses of masonry were leveled off every 12 inches, and no stone put in which reached through the wall or raised over the course of 1 2 inches. Granite, or gneiss of the most sound quality, was used. The hydraulic mortar at tunnels, and...

Informations bibliographiques