THE ROYAL SOCIETY

Otago Daily Times, Issue 22903, 10 June 1936, Page 15

THE ROYAL SOCIETY

LECTURES BY MR C. 0. HUTTON GLACIATION IN THE LAKE COUNTRY A large attendance of members of the Otago Branch of the Royal Society of New Zealand was treated last night to two interesting and informative addresses by Mr C. 0. Hutton, who is the first holder of the Sir George Shirtcliffe Fellowship, and who will leave shortly to carry out research work in England. Mr Hutton’s main lecture was entitled “Glaciation of the Wakatipu and Manspouri Regions,” and this was preceded by a short address on the Canterbury meteorite. The president of the branch (Dr A. R. Andrew) presided, and, after introducing the speaker, wished him every success in his future career. THE CANTERBURY METEORITE. Preceding the principal address of the evening, Mr Hutton gave an interesting talk on meteorites and exhibited the specimen found in Morven, South Canterbury, by Mr William Stewart, who sent it to the Dunedin Museum. Only three other meteorites had fallen in the Dominion, two in the North Island and one in Southland. In appearance, the speaker said, the meteorite was not easily distinguishable from ordinary rock, but its density was far greater. A meteorite was a portion of a heavenly body that had disrupted and flown into space. When it entered the atmosphere of the earth and flew through the air it gained heat, until it became incandescent when it could be observed by the human eye. Occasionally one was big enough to strike the earth, but it had been estimated that of the thousands of millions which entered the earth’s atmosphere only one in a million was visible to the human eyeThe speaker dealt with the chemical composition of meteorites, and mentioned that only in two places in the world were found rocks similar in formation to meteorites. One place was in West Otago, and the other in Oregon. Rock of a somewhat similar composition had also been discovered in Greenland. It was interesting to note, Mr Hutton said, that there was no element in a meteorite that was not fully known to science. The speaker expressed appreciation of Mr Stewart’s action in sending the meteorite to the local' museum for identification, and, after it had been pronounced to be a meteorite, for allowing it to remain 6n exhibition.

GLACIATION IN LAKE COUNTRY The effects of glacier action in the formation of the picturesque landscapes and interesting topography of the Wakatipu and Manapouri regions were fully demonstrated by Mr Hutton in the course of an instructive address which was illustrated by an excellent series of lantern slides.

Introducing his subject, Mr Hutton explained the formation and action of a glacier, which was a tongue or sheet of ice moving from a high to a lower level. It was the valley glacier which was the one responsible for the glaciation in the Lake Country. Moving ice was an active eroding and transporting agent. It polished surfaces like glass, smoothing and benching, scouring and plucking, ana wearing away hollows, which later became tarns or mountain lakes. The glacier gathered boulders and rocks in its course, some being deposited in moraines and some being frozen into its base to act like a rasp on the surfaces over which the ice rode. The final result of a’ glacier in a valley, the speaker stated, was to produce a U-shaped bed. Many years ago in what was known as the Pleistocene Age, Mr Hutton continued, Lake Wakatipu was full of ice, which had made its way dowp the valleys of the Dart, the Rees, and the Routeburn. It had been estimated that the thickness of the icc at Glenorchy was 0500 feet. The speaker, by means of numerous elides, traced the course of the glacier down the lake. He showed how it nearly over-rode Mount Nicholas, formed Lake Dispute, nade its way through the pass into Moke Lake, and so continued its progress to Queenstown. In its journey the glacier smoothed the surfaces of the land. leaving striatious_ in places and depositing erratic or foreign boulders in its course. Examples of the smoothing action of the ice were the Queenstown and Peninsula Hills. It was interesting to note, the lecturer remarked, that the Queenstown Domain was entirely a moraine, and contained foreign boulders and material brought down by the glacier. In fact, the well-known Scott memorial was a huge _ boulder transported by the ice from either the Ailsa or Humboldt Mountains away up .the lake. The glacier, after leaving Queenstown, had passed through the Frankton Arm and over the Queenstown Hill. It had later been divided, the major portion of the ice travelling down the lake to Kingston and the remainder into the Arrow depression. Two well-known features of the lake were the Peninsula, which way of solid rock, and Peninsula Hill, which was eroded on the upstream side and plucked on the downstream face, where the Kawarau dam now stood. The ice was not very active in the Arrow Basin and in his opinion, the speaker said, the glacier did not move down the Kawarau Gorge beyond Victoria bridge. At Gibuston stood an interesting example of the transport powers of a glacier—a large block of limestone which must have been brought down from Bob’s Cove nearly 30 miles away. It was at Kingston that the Glacier had melted and deposited all the material it had brought down in a large terminal moraine. These rocks and boulders, some smooth and some striated, could be seen to-day, and, in the valleys beyond, natural highways had been formed by the outwash gravels. Mr Hutton went on to describe how the, ice from the Hollyford came down the Greenstone Valley, crossed over the Mararoa Pass road, and thus into the Mararoa Valley, where it had formed a _ huge moraine. The Wiuton Glacier had joined the Mararoa, and the combined glacier had then united with the Oreti Glacier. The speaker traced the course of these large ice-flows, and went on to tell of glacier action on the _ landscape of the beautiful Manapouri district. The many picturesque elides showed clearly _ the smoothing and scouring work of the ice. Mr Hutton concluded by saying that the idea prevalent years ago that the entire Lake country was under an ice-cap was completely unsubstantiated. It was clear from recent observations that the glaciers were confined in the main to valleys, and only rarely had there been any 11 spilling over ” of ice over the mountain ranges. A vote of thanks to the speaker was proposed by Professor Benson, who complimented Mr Hutton on the able manner in which he had treated a subject which covered over 1000 square miles of country.