HARBOUR MATTERS.

Timaru Herald, Volume CXXIII, 9 April 1926, Page 13

HARBOUR MATTERS.

To the'-Editor of the “Timaru Herald.” Sir;.—l liave been asked several tildes why;, in my letter of the- 4th of last month; I stated that “Mr Holmes’ dissertation oil matters pertaining to our harbour, tho crux of which it is evident that he is not- sufficiently conversant, with, can only be taken ciim grano salis.” s MS’ reasons were self-evident. The. direction of the littoral current, that is the diagonal wash of the waves, on the beach as they travel up the coast and the sea for a couple, of chains outside .the surfliole, <■ do not under aqy circumstances depend on tbo, direction-’of the wind, nor dp tire waves close Inshore in any way coincide with tho wind by.: reason of irregularities in' the coastline or otherwise-. Tile large ocean rollers in our roadstead under, south-east storm conditions 'have never;' been known to be influenced by liigh winds,! or,,.any winds at ajl. if Ahoy had- ive;, should have, had,,a clean: record-, as regards wrecks. Old residents will' repl'eniber-.that the wrecks: 'always occurred -under the most perfectly calm ; weather 'conditions. The volume and i velocity'of tho masses of the sea force, passing the -end of the ■ Eastern Ex-|,,tiojisi6'ii..-.,4o.'hot,.coii¥tftutb:;'a'flittofaf. or other current; but arc simply tho regular storm waves flowing up the coast, and are not in any way increased by any wind power in tho vicinity of our; jiorjt. Neither are any of those waves back from Hashing Itocks.'Sufficiently to he noticeable to- ■ wards-tli4 vend of the Extension. A lee mole from the lUenvenue Cliff with a spur from tho Extension north-west-wards to the ship’s channel would provide excellent training walls for divert;intt.:.th@^sea;l pbwer directly on to tlie AVafmataitai Beach, and instead of haviiig- u high-laJiituig bathing ■beach there, as diagnosed by Mr Holmes, we should, in the very near future; -if the Railway Department did not forthwith protect their embankment, have to think about providing questionable bathing accommodation certainly not nearer than the golf links. The conditions about the Waimataitai Beach are serious enough now in all conscience, but training walis to deliberately divert and guide the tremendous engorging seas on. to that rapidly eroding beach would ho getting over the edge. If he tad s>cn a roaring south-easterly Bea upending its force on that beach, Mr Holmes would have understood that the miracle of miracles would have to be performed before it would be possible to form a safe bathing resort there with a treacherous surf-liole foreshore directly exposed to the fury of every sea storm. When wo study the question of the ship’s fairway, we find that there would not be the. slightest protection. It is an absolute certainty that no vessel, with a modicum of safety, could enter or leave tho port during bad weather conditions. The plea that “the wave action or scericEiii the shipping basin will be a minimum” can only be taken for what it is worth. ' If Mr Holmes is so absolutely ignorant of tho sea conditions outside the harbour, it is evident that ho (that scend not being in operation during his visit) does not know sufficient about the internal conditions to express 1 a decided opinion on such a momentous question. My knowledge of tho sea forces from before tire commencement of the concrete breakwater to .the present time, and xuy careful, oh-. . solvations /.while working among the' shipping on during all sorts and conditions of weather; have convinced me that the scend;is directly caused by.: or attributed .to; the afrtion. of->.the "Intermittent pulsations of the wave' power, that isj those so well known three successive high waves which constitute that mysterious vital energy of the ocean power that it bevoTul the comprehension of man’s reasoning powers. Those three intermittent, iv,ayqs, ..alter they have swung .found, the end of the Eastern Extension, and havo been released from the /retarding pressure of The southerly- set of tho current manifested in tho,'vicinity of our port during a heavy sea storm from the Antarctic regions,, and which lias been piioved to be sufficiently strong to hold'aifessel straining ; at her cable with .Jjer. stern to the oncoming storm accelerated in the.' mdyemeritk,,/round, the Bay arid ,drived,<’t6wfiids the .mouth of. the inner, liarbo.br, toSixpend.-'ltheir '.force.-' down • tire bf-Nb. 1 wharf, the dead water"iq the inner-»harbbur „rTT?jnatcly forming;)has it were, a compressor buffer which helps to neutralise and kill, the incoming wave-.!"-pulsations. Careful observations have tended to prove that the greatest force of the scend—which, strictly speaking, is the upward angular displacement of. a vessel—occurs at': suchregular intervals that they strikingly correspond with the intermittenec. of those three wave pulsations, and that that buffer reaction makes an inner berth the more quiescent-. Cause and effect are therefore obvious. It is simply an exemplification of that law by which Dame Nature, in her, abhorrence of a vacuum, expends her energy in attempting to overcome its apparent placidity. One of the principal laws in engineering is to rise to their fullest extent tho forces of nature, and to compel those forces, with the aiu" of artificial means, to c-arry out work that is required of them, and T.' am convinced that the nullification of tho scend can only be effected by constructing works of such a nature that they would tend to effectually divert and curb'those wave pulsations immediately after they had passed tho end of the Eastern Extension, and so prevent them

entering and expanding in the calmer waters of the Bay, and then expending their power in the inner harbour. An arm eastwards from the end of the Eastern Extension would conduce to that nullification, but Mr Holmes’s north-western spur would not. —I am, etC ’’ ‘ A. J. MORRIS. Timaru, April 3j -192 G.