THE RANGE.

Timaru Herald, Volume CXXIII, 2 June 1926, Page 7

THE RANGE.

To the Editor of “The T'imaru Herald.” Sir, —Analysatiou of the dogmas propounded by Mr John Mardcastle in his article on' tlie range question, lately published in your journal, induced me to think that ho has not studied the laws of cause and ellect, as applied to sea action, suliiciently to understand tnat there arc more '.venders connected with the causes and phenomena of-that Jaw than his philosophy has so far encompassed. 'Tne ambiguity of his postulation that the “true origin of the range” is to be found simply in the . water swirling round the end of the Extension, and by each roller sloughing olt water and energy “lrom its high level to the lower level,” defeats its own end. As I have before pointed out, the range is primarily caused by the action of the intermittent pulsations of the wave power, that is those three successive large waves so very noticeable during a heavy sea, and is only particularly manliest during a southerly or southeasterly Antarctic sea storm. AVliat is more, those waves neither drive, any extra quantity of water into the inner harbour, nor of themselves cause any current. The southerly set of the current into Caroline Hay is distinct from, but acts as an impetus to, those wave pulsations as soon as they have wheeled round the Extension. Those waves simply expend the energy of their recurrent- pulsations, with wave-tike effect, in our harbour in the form of upward angular displacements of water wli.ch constitutes the “sccnd,” and careful observations tend t-o prove that the greatest force of that sccnd, occurs at intervals which strikingly correspond with, the recurrence of those three wave pulsations. .The Greek phrase ior those waves “trikuma kakou,” the meaning ol which “the three iold wave of evil” is certainly very expressive. Nautical authorities say that “at periodical intervals there come, together, three high dominant billows, the middle one the worst, which are plainly to be distinguished from the minor rollers, and they do all the mischief to a labouring ship. Practical navigators look for these recurrent trikumata or ■triple surges of evil,' just about three times in each hour of any "heavy gale” in the deep waters of any ocean, in the comparatively shallow waters on the plateau on which New Zealand rests, they occur at very much Jess intervals of time and necessarily are not so high. Man’s reasoning powers cannot comprehend the source and nature of that mysterious vital sea energy. Though he discourses on the range, Mr Hardeastle clearly shows that lie docs not appreciate, in its true sense, the primary cause from which the source of such effect is derived, if, as lie would apparently wish us to understand, the range in our harbour is caused chiefly by the ambiguous sloughing oil of water and energy from the rollers as they pass the eiid of the Extension, perhaps lie would expect us to believe that tlie range in the inner harbour at Lvttelton is caused by a similar sloughing ofi, etc., etc., from waves swing- I ing round Hanks Peninsula The range at” Lyttelton is, L understand, sometimes more excessive than it is at ! Timaiu. In fact it is on record that the Lyttelton dredge cannot always be hold moored at the wharves thorp. Lyttelton inner harbour is situate about six miles from the ocean, with that length of a wide channel intervening, in which the range has to travel and partially expend itself before it reaches the inner harbour, whereas our inner harbour is considerably less than one mile from tiro end of the Extension. So, on a comparison, can Mr Himlcastle’s dogmas, by any force of reasoning, bo made to adjust thenattributes to moot the case of each of those ports ns readily as it can be proved that the tangible evacuee that 1 have adduced is the only feasible and vational proof of the fact that the range is caused, primarily, by those “triple .surges of 0 vll |” y 1 MORMs! May 29, 1926. .