Side of the river upon two terraces or plateaus - the first about 60 ft., the second from 100 to 150 ft., above low water - and upon hills which enclose these terraces on three sides in the form of an amphitheatre, rising to a height of about 400 ft.
The harbours are connected with the town by an embankment and railway built across a shallow, dry at low water save for a narrow channel.
When the river is high the water rolls over the main falls in one great unbroken expanse; at low water (when alone it is possible to look into the grey depths of the great chasm) the falls are broken by crevices in the rock into numerous cascades.
Above Portland, and the depth at low water to Corvallis is only 3 ft.
With a depth at low water of 32 ft.), Garvel graving dock and other dry docks.
A granite arch built in 1377 over the Adda at Trezzo had a span at low water of 251 ft.
The total length of navigable channels is about 1150 m., but sand banks and shallows not infrequently impede the shipping traffic at low water during the summer.
And upwards of water at low water of ordinary spring tides, and over 15,000 lineal feet of accommodation; the Empress dock, 182 acres, with a depth of 26 ft.
This latter portion of the river's course is tortuous, but in spite of this, and although the depth varies from only 7 to 20 ft., and in places at low water does not exceed 4 ft., it is nevertheless navigated by vessels up to 180 tons burden and proposals have been made to embank and dredge it so as to increase this depth to 8 ft.
When living near the coast foxes will, however, visit the shore at low water in search of crabs and whelks; and the old story of the fox and the grapes seems to be founded upon a partiality on the part of the creature for that fruit.