Saturday, 10 May 2014

John Hardcastle & the 140 mile beach

John Hardcastle  23 April 1899:   The 140 mile beach: Our great shingle river.  Timaru Herald p4.

"The most remarkable stream in Canterbury is surely that which claims the Rakaia, Ashburton, Rangitata, Orari, Opihi, Pareora, Otaio, Makikihi, Waihao and Waitaki as its tributaries, that stream of boulders, pebbles and sand which flows along the eastern coast for 140 miles or thereabouts; a stream which has neither bed nor bank; on which one may walk dryshod or be drowned, a boat may lie safely or be swamped or wrecked; which flows, not like water but by water; not by gravitation but against it, by fits or starts, both ways by turns, on the surface, and a part of the surface only; whose loss is not by evaporation or percolation but by trituration; - the 140 miles of shingle beach that drifts along, defines, and defends, the coast from Oamaru to Banks' Peninsula.

Each of the rivers above named, when in flood rolls along its bed into the sea smaller or larger quantities of shingle, that has been gradually brought down from every spur and every gully, ridge and cliff, in the country drained by its tributaries, -with a reservation in the case of the Waitaki. The Waitaki delivers the largest loads, but only some of its tributaries contribute to them. The glacier streams which go to form the Tekapo, Pukaki and Ohau, the three chief branches of the Waitaki, are 'silt-trapped' by lakes, and their loads of shingle, enormous ones, do not reach the sea. The sea takes charge of the shingle on delivery, bears away the mud and finer sand and distributes it over its bed, and sets its breakers to work upon the boulders and pebbles, first to heap them up on the shore, and then to ceaselessly beat and pound and grind them together, to reduce them to mud and sand that can be carried in suspension to deep water. Every wave that breaks upon the beach disturbs it more or less."

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