In one of these papers Levy formulated the requirement now generally adopted in France that the vertical pressure at the upstream end of any joint, calculated by the law of uniformly varying stress, should not be less than that of the water pressure at the level of that joint in order to prevent intrusive water getting into the structure.
Tensile stresses (indicated by broken lines on the diagram) are shown at the upstream toe notwithstanding that the line of resistance is well within the middle third of the section.
The mooring chains, weighing 22 lb per ft., are taken from the upstream end of each pontoon to a downstream screw pile mooring and from the downstream end to an upstream screw pile.
The Missouri is navigable for small boats to Fort Benton in Chouteau county, but farther upstream near Great Falls, Cascade county, to which it is navigable at high water, it falls 512 ft.
Upstream from that point, but is generally taken to embrace the whole valley from its source to a point near Jervaulx abbey, a distance of nearly 40 m., below which the valley widens out upon the plain.
In the meanwhile Banks had moved upstream from New Orleans, and laid siege to Port Hudson.
After this the ironclad retired upstream, where she was eventually destroyed in the most daring manner by a boat's crew under Lieutenant W.
Another canal, the Villoresi, drawn from the same bank of the Ticino farther upstream, is capable of carrying 6700 cub.
This width of flooring was doubled to 223 ft., and along the upstream face a line of sheet piling was driven 16 ft.
The recent investigations already referred to indicate the desirability of curving dams in plan in order to reduce the possibility of tension and infiltration of water at the upstream face.
This feature indicates that in the event of a crack occurring at the upstream toe, its extension would tend to turn downwards and follow a direction nearly parallel with the maximum pressure lines, in which direction it would not materially affect the stability of the structure.