Saturday 24 May 2014

John Hardcastle finds a Drumlin

It is generally believed that there are no drumlins in New Zealand; John Hardcastle claimed to have found one:

"It is familiar knowledge that the Mackenzie lakes have been occupied by great glaciers, whose huge terminal moraines form a series of irregular mounds, stretching for miles across the front of each lake, and serving as dams holding up these fine sheets of water. The Tasman glacier of today is about 18 miles in length; the glacier that filled the Tasman valley and Pukaki lake was about 50 miles long, and proportionately wide. And those of Tekapo, Ohau and Ahurri were proportionately large. Yet these glaciers were small, their moraines diminutive, compared to those of the Great Glacier Age. These do not appear to have left any 'terminal' moraines, such as we see in the lake dams, but some of their massive longitudinal moraines remain, eloquent witnesses to the vastness of the ice streams that piled them.
They are high and bulky ridges margining the valleys, and stretching down the middle of the original bottom of the plain. They have the form that English and American glacialists have agreed to call adfter a Scottish term, 'drumlins' - long, straight, elliptical ridges, with a steep side towards the valley in which flowed the glacier that built them up. A very clearly defined one lies along the foot of the range below Lake Tekapo, from where Edwards Creek comes out of the hills to a point overlooking the lake."   JH 1908.

Monday 19 May 2014

John Hardcastle and the Canterbury Plains

A question:  Why are the Canterbury Plains so flat?  Professor Hutton argued that it was due to the action of the sea.


John Hardcastle wrote on the Canterbury Plains at some length; the southern plains push down into his region of South Canterbury.

"King Frost resumed his reign over Southern New Zealand. Once more the action of severe frosts in the mountains caused the rivers to be overladen with shingle, and a new set of fans was spread out over the old red gravel plain, where this had not been ridged up into hills and downs above the reach of rivers. The fans thus laid down...   form the plains of today, with the connected level fillings of wide mountain valleys."

"The most remarkable feature of the Canterbury plains, I think, is the smoothness of their surface. There is nothing in our experience of river action today to explain that smoothness, which, even where the material is a coarse shingle, as on the upper Rangitata plain, required no pick and shovel work to make a track to drive a coach over. 'Old riverbeds' have not this smoothness, and the Mackenzie plain has quite a mottled appearance from the unevenness of its surface. The plains were undoubtedly laid down by rivers, but only a great sweeping rush of water could have smoothed out the current corrugations so completely. Was this a result of the Great Thaw? I think not."
 

Friday 16 May 2014

John Hardcastle and the Sands of Caroline Bay



John Hardcastle  1904  Caroline Bay: How the sand comes in.  Timaru Herald 24 September 1904

"The transformation of the southern side of Caroline Bay, from a bay of moderately deep water, margined by a narrow beach of travelling shingle upon a rocky bottom, to a broad, gently sloping and continually growing deposit of sand- from a fishing ground  and a frequent scene of wrecks and strandings, into a favourite bathing ground and site for shrubberies and a band rotunda, is a truly remarkable phenomenon, with many curious minor details.

One striking feature of the sand deposited in the bay is its remarkable evenness of grain; it is perfectly sorted, from finer sand or coarser silt. By what means is the sand so delicately weighed, brought into the bay and left there? And how and where did it all originate?"


John Hardcastle  1913  Caroline Bay: How the sand comes in: a problem and its solution.  Timaru Herald 17 December 1913

The attractive features of Caroline Bay are so numerous and so varied that persons of widely different tastes find there something to interest or please. The sea, with its freshness and infinite variety, the all-the-year-round  verdancy of lawn and shrubbery, cliff shroud of ice plant, the chromatic gamut of the flower beds, the picturesque buildings and quaint line of dressing boxes, the smooth softness of dry sand the delight of infancy, the firm footing of the tide-wetted sand that makes a peerless promenade, the beautiful freshness of ozonised sea air, the enjoyment of the holiday feeling, even for the space of minutes, as one passes along the cool beach to or from business in the dinner hour, the sense of thankfulness that so near to the scene of one's daily toil and worries one can get away from them, the pleasure of sympathising with the pleasure of others- these things are among the many that make Caroline Bay what it is so reasonably claimed to be- Timaru's best asset."







Wednesday 14 May 2014

John Hardcastle on the Moon


John Hardcastle 1917  Lunar Theories: The motions of the Moon in her solar orbit.  Timaru Herald  11 July 1917  p.3

John Hardcastle 1917  Lunar Theories: the second motion, swing in latitude.  Timaru Herald 16 July 1917  p.2


"Seeing recently... in Flammarion's 'Popular Astronomy' his diagram representing the courses of the earth and moon around the sun as long-drawn-out wavy lines, crossing and recrossing each other, with his accompanying statement that the course of the moon is everywhere concave to the sun, the humorous idea occurred to me that the motions of the earth and moon resembled those of two cyclists alternately 'pacing' each other round an enormously long and narrow racing track. Such motions are entirely different from those usually ascribed to these bodies- the earth circling round the sun in an elliptical orbit, and the moon, so to speak, 'running rings round', the earth in a smaller elliptical orbit. Struck by this difference of ideas, I set about enquiring whether the motions of the moon have been treated by anyone from the heliocentric or any other extra-terrestrial point of view; looking upon earth and moon not as planet and satellite but as a pair of planets travelling round the sun in company, and changing places as leader and follower under the influence of their mutual gravitation."

The basic idea, which JH expresses eloquently, is that the gravitational attraction between the moon and the sun is more significant than the gravitational attraction between the moon and the earth. Earth and moon are not planet and satellite but are a twin planet. This might be another first for JH; this could be the first time that the earth-moon system has been considered as a double planet. The idea was nicely explored in the 1960s by Isaac Asimov in an essay in 'The Magazine of Fantasy & Science Fiction' which, despite its name published quite a lot of serious and genuine science. Asimov, assisted by Isaac Newton, compared gravitational attractions between planets and satellites in the solar system; the simple equation f  =  mass1 x mass2/ distance squared  can be applied with interesting results. Asimov showed how the planets of the solar system dominate their satellites- with the exception of the earth-moon system, where this is not the case. JH develops this idea in two long articles in his journal of choice- the Timaru Herald (and subsequently in the Scientific American for 1919).

"Reverting to the cyclists 'pacing' motion...  Luna does some pacing, and Tellus feebly responds to the invitation to 'come on', but when Luna has dropped back to the rear to give Tellus his turn, he also slows down. Tellus in fact, maintains an almost even pace in the middle of the track. Luna races up, passes on the right, gets ahead a little, then slows down, and, observing the rule of the road [in NZ] allows Tellus to pass her, and she falls back as far to the rear as she had previously been ahead.
That it is not a case of Luna 'running rings round' Tellus will be seen from the fact that the proportions of their monthly course may be likened to a cycle track, slightly curved, two miles long, and, to give plenty of room, 120 ft wide, on which two cyclists travel together. One of them, the bigger, Tellus, has a start of 60ft, and rides in the middle of the track all the way. The iother, Luna, overtakes Tellus at the half-mile, and having swung out to the right-hsand side of the track passes him. At the end of a mile Luna is 60ft ahead of Tellus, and in the middle of the track. In the second mile Luna slackens her pace, swings across to the inner side of the track, Tellus passes her at the half mile, and at the end of the two miles that represents the month's course, Luna is again 60ft behind Tellus. This is the true order of their going, month after month, as far as concerns the apparent circling of the earth and the phenomena of the phases."

Tuesday 13 May 2014

John Hardcastle and the Pink & White Terraces

The connections may be a bit tenuous; but we will attempt to make them. John Hardcastle lived most of his life in the South Island, at Timaru, but in 1886 he was living in Napier in the North Island. He was there when Mount Tarawera erupted- and he was moved to contribute a discussion about the event to the New Zealand Institute. One of the most important consequence of the Tarawera 1886 eruption appears to have been the destruction of the Pink & White terraces. The terraces were a famous landmark and tourist attraction in the volcanic part of the North Island; a series of terraced pools formed by the deposition of minerals from volcanic waters.

John Hardcastle 1888.  The Tarawera eruption, 10th June 1886. A criticism of Professor Hutton's (and others') explanations of the cause of the eruption.  Transactions & Proceedings of the New Zealand Institute 20, 277-282.

The Tarawera discussions did not touch on the phenomenon of the Pink & White terraces- that came much later and from an unexpected direction. Robin Wooding(1926-2007) was a very talented scientist, and a grandson of John Hardcastle. He had a long and distinguished career with CSIRO in Australia and DSIR in New Zealand.  He was interested in some observations that JH had made on the Mueller glacier. JH had noticed that a stream issuing from the glacier carried ice particles with it that made a dam trapping a pool of water. The formation of the ice dam retaining the glacial water had certain similarities to the formation of the pool walls in the pink & white terraces, holding back the volcanic waters. Here was a possible mechanism for the formation of the pink & white terraces; perhaps the ice model fitted with the volcanic situation.

John Hardcastle 1920.  Deposition of ice by a glacier spring. New Zealand Journal of Science & Technology  3, 26-28.

We do not know if Robin Wooding finished his appreciation of the JH glacier studies. The mechanism as outlined in the JH paper is realistic, and possibly has not been noted elsewhere. Many of JH's observations have turned out to be original.

Craig T Simmons, D.A.Nield  2009.  The life and work of Robin A.Wooding. Trans.& Porous Media 77, 133-142.

The main areas where Robin Wooding worked were: (1) the discovery of the occurrence of fingers in the context of mono-diffusive convection in a porous medium and an early body of associated papers on convection in porous media, (2) the development of a novel hydraulic model for the catchment-stream problem and (3) the mathematical solution to the problem of steady infiltration from a shallow circular pond that formed the basis for the disc permeameter method. The idea of steady infiltration from a shallow pond brings us round to the pink & white terraces and to JH's observations on the Mueller glacier.

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."

Friday 2 May 2014

Raeside loess map

To complement the Hardcastle material; to show the location of Timaru

John Hardcastle & the Moa Hunters

John Hardcastle 1908  Notes on the Geology of South Canterbury.  Timaru Herald  64p.  "There is some rather curious evidence of the early occupation of South Canterbury by man. A popular picnic resort, a few miles above Pleasant Point, is known as Noah's Ark from the number of aboriginal drawings that are seen there, on an overhanging cornice in a limestone rock. These drawings are well preserved, being protected from the weather by the overhanging of the cliff, and they are also protected from destruction by mischievous hands, by being out of reach. When these drawings were made the riverbed must have been at least six feet higher than it is today along the foot of the 'Ark', and this is some feet above the present river...

Relics of a moa-hunters camp existed at the northern end of Dashing Rocks, but they have been nearly all washed away by the sea. There are still some remains of ovens left, with fragments of charred moa bones and flakes of grey siliceous stone in them. The later Maoris must have also camped on the same sopt, as some articles of greenstone have also been found there."

Moa hunters near Timaru. Cave art- wall of Blacklers Cave, Pleasant Point, in the vicinity of Timaru, South Canterbury