A Treatise On The Principles And Practice Of Dock Engineering

12 DOCK ENGINEERING. présent condition and prospects of the river are thus stated by the Engineer, Mr. W. M. Alston *:— “The deepening and widening of the river is still going on, the constantly increasing draught of vessels demanding more depth, and more ‘depth involving greater widths in order that the banks may stand. Dredging is presently being executed to 20 feet below extreme low watei, or 22| feet below average low water of spring tides, corresponding with about 32| feet at high water, spring tides, at Port-Glasgow, and 33| feet at high water, springs, at Glasgow; and with this depth, the bottom widths range from 120 feet at the River Kelvin to 500 feet at Port-Glasgow. Out of the 16 miles of channel between the harbour and Port-Glasgow, about 10 miles—not continuous—may be said to have attained this depth; while in the remaining 6 miles the depth varies from about 19 feet to 22-1 feet below average low water of spring tides.” Owing to the comparatively small range of tides—about 111 feet at springs and 9 feet at neaps—it has not been deemed necessary to equip the Glasgow docks with gates. They are, therefore, properly speaking, tidal basins in which the water is free to rise and fall with the tide. The first dock, the Kingston, with an area of 5^ acres was opened in 1867. The Oueen’s Dock was completed in 1880, and added 33^ acres to the available accommodation. This dock is situated on the north side of the river. Parallel to it on the south side has been constructed, between the years 1892 and 1897 the Prince’s Dock, with an area of 35 acres. These constitute the present extent of the dock accommodation at Glasgow. Developments, however, are in hand, and a dock of 16f acres is in course of construction at Clydebank, 6 miles below Glasgow Bridge, for the service of the coal and mineral trades. The shipping at Glasgow, which in 1810 only registered 24 sailing vessels and 1,956 tons, in 1900 had increased to 1,605 sailing and steam vessels with a tonnage of 1,582,229. The vessels arriving and clearing at Glasgow in 1900 numbered 21,800, with a tonnage of 7,461,417. The Port of Hamburg. The leading port of the Continent conducted all its loading and unloading operations prior to 1866 by means of open barges, the ships being moored to dolphins, arranged in long rows in natural bays, along the banks of the Elbe, or in the river itself. The earliest basins to be constructed were the Sandthor (24 acres), and the Grasbrook (161 acres), and these were brought into existence between the years 1860 and 1870. In 1881, the port joined the Customs Union of the German Empire, and a period of great activity in dock construction commenced. From the year 1884 onwards the port has been extended by the formation of the Beacon Basin (44 acres), the Hansa * Alston on “ The River Clyde and Harbour of Glasgow,” International Engineering Congress, Glasgow, 1901.