MS 1003 T.G. Taylor Series 12. Box 48. F. Debenham, British (Terra Nova) Antarctic Expedition 1910-1913: Report on the Maps and Surveys (London, 1923)
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MS 1003 T.G. Taylor Series 12. Box 48. F. Debenham, British (Terra Nova) Antarctic Expedition 1910-1913: Report on the Maps and Surveys (London, 1923) Map VII The Ferrar Koettlitz Region. Scale 1:200,000; Projection: Simple Conical 72. From the point of view of the geologist and the ice specialist, this is perhaps the most important map of the series, and although a good part of it is in broken line, that is to say, based on sketch surveys, it is hoped that it will be of value for their purposes. Sources and Framework: The basis of the map is that produced by Lieutenant Mulock from the surveys of Armitage and Ferrar and from some observations of his own on the Discovery Expedition. Minor corrections and additions have been made to that map where later data were available, while the part north of the Kukri Hills and on the upper Koettlitz Valley is new. The original map was a compilation, and the present one is a compilation of a series of more or less independent local surveys made from rounds of angles with the theodolite by C.S. Wright. To plot these angles a selection of points had to be assumed correct, and choice was made of Mount Lister, the Pimple and Mount Higgins for the coastal strip, and Obelisk and Knobhead Mountains for the Ferrar and Taylor Glaciers. It was obvious when fitting the observations that there were bad discrepancies in the positions of these points taken from the original map, and a certain amount of arbitrary adjustment was necessary. Such adjustment seriously discredits the map as a whole, but does not greatly affect its value for the purposes stated above. The map, as published, is the result of a six weeks’ journey up the Ferrar and the Koettliz Glaciers in the autumn of 1911, when other subjects for observation than [73] survey measurements were the chief duty of the party. In consequence, the sources for plotting the detail are extremely varied. Photographs, sketches, small contoured plans sketched by eye by the writer, and other somewhat untrustworthy records have all been used, involving considerable labour without a corresponding satisfaction at the result. It is thought, nevertheless, that for individual valleys and local detail the errors will not be found to be unreasonably great, and the map perhaps fulfills the first requirement, to constitute an improvement on the former one. The plane table was not constructed then, and only the coastline by Cape Bernachhi comes from the sheets surveyed in the following year. It will be seen from the general relief that the district presents no difficulty from a surverying point of view and could be mapped to a similar scale without plottable error by a skillful plane-tabler in a few weeks, even without the assistance of theodolite control. It should be noticed that the Upper Ferrar Glacier, which was not visited by the 1911 party, has been amended. This is because the original sextant survey figures of Ferrar were found and replotted in the light of more accurate local knowledge than Mulock had. A word with regard to the naming of the features on this map and that of Granite Harbour is necessary. The party responsible for the survey work adopted the useful custom of giving names rather than numbers and letters to all distinctive features met with. This simplified references in the notebooks and in conversation, the principle in this case being to endeavor to name a feature from its appearance and, failing that, to fall back upon a geologist – two of the party belonging to that fraternity. These field names were, of course, to have been replaced in the final maps by others chosen by the authorities of the expedition. Owing to the death of Captain Scott and also to the need of haste in bringing our the preliminary maps for the narrative, this was never done. None of the Discovery names have been altered, but some have been somewhat delimited, for instance, the Ferrar Glacier, first surveyed and examined by Ferrar, has now a series of named glaciers leading to it or from it, including the Taylor Glacier, called after the leader of the 1911 party. Routes and Special Features No routes have been inserted on the map, but one or two remarks on the subject are called for in connection with travelling on the Koettlitz Glacier. The detail of the rough ice on the lower glacier is the result of give days’ very slow progress over some 20 miles, at the end of which it was found that there was a smooth and easy at the northern side over a wide thaw- stream. The easy route had indeed been found and used by a Discovery sledge party, but the facts not having been published or mapped, it had to be re-discovered. Owing to this delay, an important duty on the programme of the party could only be partially fulfilled. It was intended to investigate throroughly the peculiar longitudinal valley below the Royal Society Mountains, called in the Discovery maps, Snow Valley. Since it lies just where the entry of “Foothills not surveyed” occurs, no strong evidence on the subject is given by this map. From observation – in dull weather – from the top of Terminus Mount, however, it was seen that it did not exist as a since valley, but rather as an indefinite group of low foothills with some hint of low valleys between running away from and not parallel to the escarpment. There are certain points on the map which were plotted with special care with a view to comparative measurements to be made in the future. The first of these is the snout of the Taylor Glacier, a glacier which may perhaps be regarded as a suitable indicator of the supply of ice from the plateau, since it fed from there and not from neighbouring slopes and, unlike most Antarctic outlet glaciers, fails to reach the sea. The snouts of the Canada and Commonwealth Glaciers in the same valley were fixed as to extent by plane table and may be regarded as fairly correct. Those of the glaciers south of the Ferrar Valley are less accurate, the Hobbs and Davis being the best. The junction of land and sea ice off Cape Chocolate is another important line; it was not surveyed but cannot be more than half a mile in error. It should be noted that this map replaces one of the same area published with the narrative of “Scott’s Last Expedition,” which was compiled at short notice and included many errors since detected. .