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- The Journeys
- Instruments and the Performance of Magnetic Observations
- Extreme challenges on the trail
- Ancilliary science
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| Detail from Mulock (1904) showing “Barrier Journey” path of Bernacchi & Royds from Ross Island towards the south-east.
When Mawson was preparing his Aurora expedition he recognised that the ongoing problem was that all magnetic observations for the determination of the location of the magnetic pole had been made at sea or from the south-eastern quarter. Mawson wanted to improve the estimate of location of the pole by sending one of his summer 1912-13 sledging season parties from Commonwealth Bay (Cape Denison) base to the locality of the pole. The location of the base at Cape Denison allowed an approach from the north-west for the first time. Webb’s journey anticipated a region of about 40 miles diameter for the locality of the magnetic pole, so that distance was added to the prospective total to allow crossing over the central area. That would have been an average of twelve miles per day for the whole journey without a margin for weather, surface conditions, navigation errors, rest days or equipment failures and misadventure. Webb described the objective of the trek as follows: Our journey was intended to be comprehensive geographic, geodetic and geo-magnetic exploration. Complete absence of any tangible evidence of “mother earth” left us concentrating on the magnetic program which aimed at full determination of the terrestrial magnetic force to international standards every 50 miles. Each of such stations involved sun observations by theodolite for latitude, longitude and azimuth (true meridian): determination of the magnetic meridian by trough needle, of the inclination by 4 dip needles, and of the total force by 2 weighted needles… (Webb, 1965: 6) More generally, the objective was to sledge to the South Magnetic Pole by approach from the North-western direction. There were no prior observations from this quarter, so any observations would add to the body of knowledge regarding accurate location of the pole. Route of the South Magnetic Pole party of Webb, Hurley and Bage, 1912-13 (Webb & Chree, 1925: 37). The quest for the south magnetic pole closed initially in January 1909 when Douglas Mawson, Professor Edgeworth-David and Alastair Forbes MacKay reached the locality of the southern magnetic (dip) pole at 72° 25' S, 155° 16' E, during Shackleton’s Nimrod expedition. On that occasion Shackleton’s (unrealistic) instructions were to: 1/ carry out Magnetic survey and sledge to the Magnetic Pole 2/ carry out a general geological survey of the coast of South Victoria Land 3/ investigate the economic geology of the ‘Western Mountains” and Dry Valleys. Branagan described it as a “Nightmare Journey”, partly because of the limited time available to complete the tasks but also the quantity of provisions, food and equipment required two sledges for the three-man team, meaning much of the distance was only covered by relaying (Branagan, 2005: 181). The Journeys Bernacchi’s Barrier journey departed from Hut Point on December 10, 1903. The complement made up of six men. Royds and Bernacchi were the “officers” (scientists were considered equivalent to officers on Discovery) and the Petty Officer Jacob Cross, Corporal Gilbert Scott, Leading Stoker Frank Plumley and the ship’s cook, Charles Clarke. The total load hauled was 1037 lbs. on two sledges, an average of 173 lbs. (78.5 kg) per man. Bernacchi anticipated travelling 200 miles in the thirty days available to them. After turning the corner around Cape Armitage they headed south-east across the Barrier into completely untrodden territory. On 28 November, after eighteen days travelling, the party under Royds’ command turned for home at 79° 35’ 2” S, 175° 55’ 30” E, after making a complete set of magnetic observations and various meteorological and glaciological activities, including air sampling and taking ice crystal samples from a deep snow pit. They had travelled a “distance of exactly 155 miles = 178 statute miles” (286 kilometres). Bernacchi describes the landscape thus: “At the present we see nothing, on our horizon the barrier is one uniform dead level, no inclines nor declines & scarcely an irregularity” and “One huge white waste all around with less diversity than the Great Sahara desert” (Bernacchi, 1903b). The return journey was a bolt for home and is barely recorded by Bernacchi. The return was characterised by following winds that allowed use of the tent floorcloth as a sail on the sledge. The party’s total distance was 356 miles and they averaged 10.2 miles per day (13.2 Km) for the journey (Skelton, 2004, p. 191). They achieved a significant amount of scientific work in spite of the nine hours daily sledging and the usual time spent making and breaking camp (Bernacchi, 1938: 86). Webb’s party departed exactly nine years after Bernacchi, on 10 November 1912. Webb’s party consisted of only three men, although a support party led by Dr. John Hunter assisted them initially. Their challenge was to complete the journey and return to base to meet the ship on 15 January 1913. Webb estimated they could travel 400 miles out from the base and cross the region of the magnetic pole. This would require an average of 12 miles per day. The load hauled by the trio initially (before establishing depots) was significantly greater than Bernacchi’s party at ~270 lbs. (122.5kg) per man. Two depots were established on the outbound trek at 67 then 200 miles. They knew the strong wind would be contrary to their direction of travel initially and they devised special crampons and depot flags to handle the conditions. The party of three made the outward journey to a point where the dip was recorded as 89° 43.3’, at 70° 36.7’ South latitude and 148° 14’ East longitude on 21 December, 1912, short of their goal, the nearest point of vertical dip. Their final estimate of the location of the magnetic pole was “…the nearest position of vertical dip calculated as some 50-60 miles South-east of station 7, about latitude 71° S, longitude 150.3° E” (Webb and Chree, 1925: 40). Webb, Hurley and Bage returned to Cape Denison on 7 January, 1914. The magnetic pole journey had taken a total of 62 days, 42 outward and 20 on the return. The outward route was retraced to allow repetition of the magnetic observing stations, in contrast to Bernacchi and Royds who did not take such comprehensive observations during their return. One record days run was 42 miles on 8 December. After this the sledge meter succumbed to the harsh conditions and dead reckoning was undertaken by counting steps. Instruments and the Performance of Magnetic Observations Both parties took regular sets of magnetic observations. Bernacchi took them each three days whilst Webb took them each 50 miles travelled. Both expeditions had a variety of “portable” observing instruments for use on sledge journeys. They comprised a significant part of the weight to be shifted, and man-hauling was the only transport option. In the case of the Discovery, all the adult sledge dogs had perished on Scott’s southern journey in the previous season. Royds stated that the Barrow dip weighed 18 lbs. (~8 kg.) and its tripod added 10 lbs. (4.5 kg.) to the sledge weight (Royds, 1903). This is a lower estimate than the kit used on Armitage’s 1902 trek into the mountains to the west of McMurdo Sound during which he discovered the Polar Plateau. In the field Bernacchi used the Barrow dip circle in preference to the Lloyd-Creak dip circle that had given Armitage trouble on the outbound voyage. While sextants are much lighter than theodolites, they are more prone to error when used in Antarctic conditions. Bernacchi noted that, at the end of each third day’s sledging he took his full round of magnetic observations in the tent, usually before cooking and camp preparations commenced. In addition, Bernacchi was making the time to perform all the necessary (and onerous) calculations related to position finding and the magnetic observation results. The navigation calculations alone required sextant observations in the morning and afternoon for longitude, and midday, solar zenith measurements for latitude. Supplementary information from the bearings to landmarks was irrelevant in this case as, for much of the journey, they were on the Barrier where there are no discernible features from which to take bearings. Bernacchi was troubled by snow blindness from time to time and comments on his state of exhaustion and constant hunger. The following segments from one day’s entry (17 November, 1903) are typical: Tried to get sun sight at noon for latitude but failed through cloud obscuring sun… Took sight for longitude about 5.30 PM but not the best through sky being partly cloudy…After supper took set of magnetic observations in tent. Both dipping needles and total force. Dip has increased (sic) to about 85° 46’ & total force appears to have considerably decreased indicating increase in horizontal force. Lat. approx. 78° 33’ South by 170° 22’ 15” (Bernacchi, 1903a) His comment that the dip has “increased” is in error as the previous dip measurement on 14 November stated: “Magnetic dip about 85° 58’ ”, so the dip, as expected (moving away from the magnetic pole) has decreased. Webb provides the most succinct description of conditions and operations during field magnetic observing activities in his memoirs of the journey. Dead reckoning was used to determine their approximate location. Then each station required precise determination of latitude, longitude and azimuth (true North), then determination of the magnetic meridian, then inclination by repetition with four dip needles. For the field survey and for the magneto-graph control observations, a Kew pattern dip circle was used. Measurements were also made for vertical and horizontal force using two intensity needles. Problems included condensation of vapour on the instruments from breathing in tent or ice hole, so observers often tried to hold their breath to diminish this effect. Each full set of observations entailed a minimum of 2½ hours actual observing, when 250-300 instrument readings would be made: at the extreme south station, where dip in planes at right angles had to be followed, the readings were nearly doubled. When allowance is made for unpacking, setting up, organising windbreaks and waiting for workable conditions of visibility or wind, each station absorbed at least 4 hours-rather a back-breaking feat of endurance for the observer and perishing cold for the recorder who always had my profound sympathy. (Webb, 1965: 5) Webb’s memoir of the sledge further describes care required by the operator of a dip circle in the field and some challenges faced in the interests of quality results. He described the dip-circle thus: The dip-circle is a delicate mechanical instrument, depending for precision on the skill, care and experience of the manipulator, even in a favourable environment. When competing with low temperatures and high winds involving dust, snow and ice, these attributes are at a premium. Because of its design (for use on ship-board), the Lloyd-Creak type is the more difficult to handle and is less dependable for accurate results than the Kew. (Webb, 1965: 2-3) No opportunities were wasted. During a white-out when travelling was impossible (5 December), Webb built a snow shelter and carried out a series of observations over a 24 hour period to supplement the already onerous regime of observations. Extreme challenges on the trail Amongst the particular challenges faced by both these sledging parties was daily navigation that was critical for way finding and for the scientific program. Bernacchi was using a sextant and an artificial horizon to determine position, as way finding on the Ice Barrier was no different to navigation at sea, there being no landmarks for reference or any visible horizon. Royds’ personal diary notes on 15 November, about 40 miles from Hut Point: Surface improving but absolutely nothing in sight before us to the SE, excepting level expanse of snow with practically no irregularities. At 5pm dark object was seen some distance away on surface. On picking it up proved to be an empty plasmon paper bag. Evidently blown from the Bluff direction from one of the sledging parties to the South. Then on 26 November “nothing to steer by except the wind and drift over the ski” and on the 27th, “Absolutely no horizon, cloud, sun or sastrugi visible” (Royds, 2001). The Barrier journey was cut short slightly as on 7 December Jacob Cross noted one of the oil drums had been leaking through a rust hole, so their diminished fuel meant an early return to Hut Point. Webb’s account resonates Royds’ diary entries: “In the whole of our 600 miles out and back, there was not one noteworthy landmark other than the Nodules” hence for navigation and location they relied totally on observations of the sun. On the trail the compass was of little practical use as it was sluggish being close to the magnetic pole (horizontal force was minimal) and the declination shifted a great deal meaning that compasses were of no utility for wayfinding. On one occasion the declination shifted 90 degrees in 11 miles. The difficulty of navigating became life threatening for Webb’s party near the end of their journey. On 6 January in white-out conditions they struck trouble, being unable to locate the 67 mile depot. They reduced rations to “Half a biscuit with a little butter, small pieces of chocolate and a thin brew of tea” then on the 7th they lay all day in their bags due to poor visibility. On 8 January at 3 am, although it was clear they could not locate the depot so they decided to undertake a forced march back to base. They had “a ¼ ration hoosh to commence, then after that 1/6th sledging ration, absolute alcohol and a few raisins”. They discarded all weighty items including the dip circle (lent by the Christchurch Observatory) and tripod. They then sledged 54 miles in two days on 1 and 1/3 of a day’s ration, against a 60 mph headwind, navigating by home made sun compass and including the traverse of the crevassed zone at the head of the Mertz Glacier (Webb, 1965: 13). Ancilliary science Bernacchi’s Barrier journey yielded some additional scientific results. Aside from Royds’ meteorological observations on the trail, he dug snow pits in which he sampled temperature and described the compressed snow at different depths of the Barrier ice. Sterile air samples were procured and sealed into test tubes, although the fate of those is unknown. Royds also found strong evidence that the Barrier is floating, even far from the junction with sea ice. By suspending recording thermometers deep into crevasses (19 fathoms, or about 30 metres), they determined that the temperature rose to near seawater temperature far down within the crevasse, indicating an ice/water interface (Yelverton, 2000: 286). In terms of geography they showed the nature of the Barrier to the south-east to be similar to the route taken the previous summer by Scott, Shackleton and Wilson on their southward trek, the first sortie away from coastal Antarctica. Similarly, Webb’s party showed that the route to the magnetic pole from the north-west was little different to the polar plateau climb described by Mawson, David and Mackay in 1908. Webb’s magnetic pole journey also yielded some anciliary science on 27 November 1912 when Bage dug a snow pit to examine the stratigraphy. Outcomes In general the quality of data from the Antarctic magnetic observations improved as the “Heroic Era” progressed. The coverage of observing sites improved. For example the results from Bernacchi and Colbeck’s observations on the Southern Cross were from a single location (Cape Adare) that was heavily affected by ferrous substrates. The Discovery followed and some observations were made at sea, some at the base station and some during sledging journeys in the field. Shackleton’s Nimrod expedition included the first attempt to sledge to the locality of the magnetic pole. Scott’s Terra Nova utilised multiple observing stations (Cape Evans and Cape Adare) as well as sledge journey observations. Mawson’s Aurora did likewise, including Frank Wild’s far western party in Queen Mary Land in the regime of observations, although the conditions there were challenging. A snow hut was built when the observing tent was found to be inadequate and no continuous recording apparatus was available. Magnetic observations were also made at Macquarie Island base and on all of the numerous sledge journeys made magnetic observations part of their routine. Scott’s Terra Nova rectified the deficiencies of the Discovery program. Notably, the coordinated magnetic observations during so called “term hours” that had gone awry on the Discovery due to an error in the manual for the expedition. This regime was repeated during 1911 and 1912 with the cooperation of 36 world-wide observatories, compared to four only in 1902. The instruments improved significantly during the period in question also. Bernacchi did not have the benefit of the self-recording Eschenhagen magnetometer when he was on the Southern Cross expedition. The instrument was invented and only became available in 1901 in time for use on Discovery and Gauss. They were very reliable so were used on later expeditions such as Aurora and Terra Nova. The Lloyd-Creak dip circle had been developed for the determination of dip and intensity at sea specifically. It was available for use to both the Discovery and Gauss as part of their collaborative magnetic observing regime. Initially it was a failure and Webb attributed Mawson’s failure to reach the magnetic pole in 1909 partly on the vagaries of the Lloyd-Creak. The Carnegie Institution of Washington, D.C., that shared the world lead in magnetic research with Potsdam’s Observatory, overhauled the design of the Lloyd-Creak instruments that were then used with success on the Aurora expedition in particular. Improvements are discussed in the magnetic report of the Australasian Antarctic Expedition where the improvements to the dip circle are described. The agate surfaces for the needle pivots were replaced with jeweled cups. This reduced the problem of pivots shifting (especially when used at sea) but in polar conditions a new problem emerged, that of ice build up in the cups that affected free swing of the needle. In general the later version gave good service in harsh conditions, although the Lloyd-Creak instrument was finally abandoned for high precision polar work, due to the formation of frost in the jewelled bearings (Webb and Chree 1925: 25). The recruitment and training of experienced, qualified physicists also improved during the “Heroic Era”. Bernacchi was recruited to the Southern Cross after spending two years being trained in astronomy, navigation and magnetic observing at the Melbourne Observatory. He had mostly been schooled at home due to isolation on Maria Island on Tasmania’s east coast. So he was young, inexperienced and without formal qualifications when recruited. On the Southern Cross Bernacchi was overstretched, having to take care of all meteorological observations, most photography and sharing the physical observations with Lieutenant William Colbeck. A thin volume of magnetic results was published as observations were made on only “about fifty separate days at Cape Adare” (Royal Society, 1903: 3). The observations made on-base at Cape Adare were made under extreme weather conditions using a tent only as an observation post, and in a locality surrounded by “basaltic cliffs” and “…in the immediate neighbourhood there were numerous blackish pebbles which appreciably influenced a suspended magnet when brought near to it.” There were no field results as Cape Adare is land locked by steep mountainous terrain and mostly open water, even in winter making travel off-base almost impossible. A further source of uncertainty was the loss of the “deflection bar” on the homeward journey. This device was used to determine the magnetic field strength, and as the locality had a low horizontal field strength, out of the ordinary observing techniques were employed which should have been standardised against the deflection bar back at Kew Observatory from where the instruments had been loaned and calibrated. (Royal Society. 1903: 2). Incidentally Borchgrevink also mislaid all of the notebooks and illustrations of Nicolai Hanson, the zoologist to the expedition who passed away during spring 1899 at Cape Adare, thus diminishing the value of the collected specimens. Bernacchi was subsequently recruited to Scott’s Discovery only a fortnight before the ship sailed, as the incumbent (William Shackleton) had argued with officers (possibly about arrangement of the tinned food below the magnetic observatory on the ship) and been dismissed as medically unfit. Bernacchi had to quickly get himself trained in use of the newly invented instruments at Potsdam and Kew and become familiar with the collaborative observing regime planned in concert with Drygalski’s Gauss and a handful austral observatories. Mawson, on Shackleton’s Nimrod was at least a passionate and dedicated scientist, although not a physicist. He was a geologist lumbered with responsibilities as physicist to the expedition on short notice. Although the 1908-09 trek to the Magnetic Pole was a first, there was no follow up regarding publication of the full results of the magnetic observing program until Mawson integrated them in the “Field Results” chapter of his Australasian Antarctic Expedition volume on Terrestrial Magnetism published in 1925. Scott’s Terra Nova had a comprehensive scientific program and many deficiencies from the Discovery were rectified. Many of the instruments were the exact same ones used by earlier expeditions but the scientific staff were hand picked by Edward Wilson and well trained. Dr. George Simpson and Captain Charles Wright were recruited as magnetic observers. Simpson had actually been the first choice as physicist for the Discovery expedition but had failed the medical examination at that time. Careful attention to staff recruitment and training was also a feature of Mawson’s Aurora. Webb was probably the best trained of all magnetic observers of the era. One possible exception was Bidlingmaier on the Gauss, who became a Professor of Physics before his untimely death at the start of the First World War. Webb had comprehensive training as a field observer of the Carnegie Institution of Washington, D.C., U.S.A., and was schooled by Dr. J.M. Baldwin of Melbourne Observatory to conduct a magnetic observatory with self-recording instruments at the main base (Webb, 1975). On Discovery there were numerous flaws in the at-sea and the Hut Point base station observations and much of the data was discarded, or reported with caveats about precision. These failures are discussed in detail elsewhere (Atkin, 2012) but the sledge journey results that improved the determination of the position of the magnetic pole were sound. Royds referred to Bernacchi in his diary entry for 8 December “…no joy after a hard day’s work but he is very keen on the results and it is worth the agonies of the present time to get satisfactory and interesting observations”. Bernacchi wrote himself on the trail on 28 November “These series of magnetic observations taken on a prolonged line will be very helpful in calculating the position of the South Magnetic pole, as they are free from local attraction” (Bernacchi, 1903: 11). Critical analysis by the American Geophysical Union of Bernacchi’s determination of the South Magnetic Pole position (written in 1908 as part of the review of the published Discovery results) stated “agreement between position calculated from declination results and inclination results is remarkable.” The magnetic pole was determined to have a radius of around 38 miles with 72° 52’ S, 156° 30’ E being the central point (American Geophysical Union, 1908). Following the Discovery, Shackleton’s Nimrod was the next expedition to the locality of the Ross Sea and with an interest in the magnetic pole. The great analyst of Antarctic history, J Gordon Hayes refers to the magnetic pole journey of Mawson, David and MacKay as “One of the great journeys in polar history”, but this refers more to the geographical achievement than the scientific outcomes. They trekked 1260 miles (2028 km) in 109 marches over 122 days. The magnetic pole was determined to be ~420 miles (672 km) from Cape Royds but the route was not direct and there was a great deal of relaying that tripled the actual distance travelled over some sections. They climbed to 7350 ‘ altitude (~2100m) and endured temperatures as low as -19° F. They measured 89° 48’ dip (almost 90°) at their turn around point at 72 ° 25’ S, 155 ° 16’ E. This trip remained the longest unsupported man hauled journey for many years (Hayes, 1928: 158-160). During the journey Mawson was reading an advance copy of the Discovery Magnetic science volume (freshly published) and was dismayed to realize that the magnetic pole by his determination was about 40 miles further inland than reported by Bernacchi (Riffenburgh, 2004: 239). It was “a considerable distance to the north-west of the location assigned to it by the British Antarctic Expedition, 1901-04.” In the light of this and the need to return to meet the ship “no effort was made to secure a high degree of accuracy in the case of stations 7 and 8” (those closest to the SMP locality (Webb & Chree, 1925: 51-52). The precision of locating the magnetic pole increased with each subsequent expedition. Webb relates in his memoir that analysis by Dr. Coleridge Farr (long standing Director of the Christchurch Observatory and magnetic specialist) determined that the location of the magnetic pole by his 1912-13 party was the most accurate of all prior estimates (Webb, 1965: 9). This supports the trend of improvement over time for magnetic science during the “Heroic Era.” Publications The quantity and quality of expedition scientific reports could be a proxy for the value of the scientific work carried out in Antarctica. As mentioned, the magnetic report from the Southern Cross was scanty. The Discovery report was published in 1909 at a time when interest in polar exploration was focused on claims of Peary and Cook regarding the North Geographic Pole and when Shackleton was launching his Nimrod expedition. There was little interest except amongst the scientific community about the volume and the numerous failures and flaws were of little interest to the public. There was one volume of Magnetic results (Royal Society, 1909) and one of Physical Observations (Royal Society, 1908). Shackleton never arranged publication of a volume of magnetic observations as a result of the work on the Nimrod expedition. He did not appear to have an interest in science except when it was a pathway to procure expedition funding. The data was finally published within the volume of magnetic science from the AAE in 1925 (Webb & Chree, 1925: 50-52). The First World War intervened to delay the scientific publications from both Scott’s Terra Nova and Mawson’s Aurora expeditions. The copious volumes of the former are often quoted as a justification that Scott was a scientist at heart, but the preparation of results and their publication really came about through the abundant funding resulting from donations to support the families of the explorers who perished. There was even sufficient left over after publication to establish the Scott Polar Research Institute in Cambridge. Mawson struggled for years to get all the science worked up and published, and it was only possible through various deals ha was able to broker. The copious output was a testament to his commitment as a scientist. Similarly, the numerous volumes of quality scientific reports from Drygalski’s Gauss were brought to publication through the post-expedition fostering of the material by Drygalski himself. These examples demonstrate that the published scientific reports are not a reliable indicator of the quality of extent of scientific work on an expedition. 
The three volumes of Earth Magnetism Scientific reports (red covers) from Drygalski’s Gauss with the expedition narrative above (grey cover). Conclusion Professor John Walter Gregory was the initial choice of scientific leader for Scott’s Discovery expedition before Sir Clements Markham caused the falling out between the joint sponsors, the Royal Society and the Royal Geographic Society. He was an eminent geologist, an experienced expedition leader and had some relevant Arctic experience. He showed insight into polar field science when he wrote that man-hauling sleds and performing scientific surveys were incompatible. Man-hauling exhausted the participants, dulling their senses and reducing their capacity for inquisitive observation or scientific activity: “Secondly, one cannot expect men who are harnessed to heavy sledges to keep sufficiently alert mentally to observe accurately and solve the new problems that will be presented to them. Travellers have often been blamed for errors due to their having seen things with perceptions blunted by continued manual labour.” Gregory also commented on the need for shelter and rejected Peary’s ideas that tents are unnecessary. The scientists needed the capacity to write up daily results and observations in an environment that was conducive to intellectual activity (Gregory, 1900). Given these insights it’s surprising that any valuable magnetic observing was possible during the rigorous journeys described above. In conclusion, the advances in magnetic science during the first forays onto continental Antarctica can be attributed to the following factors: Improved leadership and governance of the expedition, that encompasses better planning and preparations that ideally are informed by personal experience or consultation with others. Recruitment, training and the development of skill and knowledge in competent scientific staff Improvement in Instruments and procedures More attentive post-expedition handling of data and collections and the fostering material through to publication Guidance from the Carnegie Institution Improved understanding of logistics requirements A shifting intellectual landscape Better coordination between expeditions and fixed observatories In spite of the significant advances in instruments and procedures, and the successful outcomes of the sledging journeys for science described here, the source of terrestrial magnetism and the reasons for phenomena such as shifting magnetic dip poles and the relationship between space weather and magnetic perturbations were still mysteries in 1914. However, improvements in the performance of Antarctic magnetic science between 1898 and 1914 contributed to the ultimate unravelling of these mysteries. With regards to the location of the magnetic pole it might be useful to consider the metaphor of a river. It increases knowledge to learn the source of a river, and also where it ultimately runs into the sea, but those two facts do not necessarily tell you anything about the watercourse between those points. So it is with terrestrial magnetism. There is much more to know than the location of a magnetic pole, but establishing that location is a good starting point for the production of deeper knowledge.
Expedition 1901-04, The Polar Journal, 2:2, 200-218. Bernacchi, L. C. (1903a). Bernacchi Antarctic Journal Volume 4, 10 November 1903 to 13 March 1904. Cambridge: Thomas Manning Archive, SPRI, MS/353/3/4; BJ. Bernacchi, L. C. (1903b). Sledging Diary, 10 November 1903-15 December 1903. Lincoln, NZ: Palmer family archive of Bernacchi material. Bernacchi, L. C. (1938). Saga of the Discovery. London: Blackie. Branagan, D. (2005). T.W. Edgeworth David: A Life-Geologist, Adventurer, Soldier. Canberra: National Library of Australia.
Geographical Society Archive, RGS/AA/4/1/3. Gurney, A. (2004). Compass: a story of exploration and innovation. New York: W. W. Norton. Hayes, J. G. (1928). Antarctica: A Treatise on the Southern Continent. London: The Richards Press. Jonkers, A. R. T. (2003). Earth's Magnetism in the Age of Sail. Baltimore, London: The Johns Hopkins University Press. Mawer, G. A. (2006). South by Northwest: The Magnetic Crusade and the Quest for Antarctica. Kent Town: Wakefield Press. McConnell, A. (2005). Surveying terrestrial magnetism in time and space. In E. C. Nelson. (Ed.). 2005. A Century of Discovery: Antarctic Exploration and Southern Ocean Science, Archives of Natural History 32(2). pp. 346-360. Mulock, G. F. A. (Cartographer). (1904). Map Showing the Work of the National Antarctic Expedition. London, Royal Geographical Society. Ross, J. C. (1847). A Voyage of Discovery and Research in the Southern and Antarctic Regions, During the Years, 1839-43. Vols. 1-2, London: John Murray. Royal Society. (1903). Magnetic Observations: Reduction of the Magnetic Observations taken during the “Southern Cross” Antarctic Expedition, 1899-1900, mainly at Cape Adare, Lat. 71° 18’ S., Long. 179° 9’ E. London: Royal Society of London. Royal Society (Ed.). (1908). National Antarctic Expedition 1901-1904: Physical Observations. London: Royal Society. Royal Society. (1909). National Antarctic Expedition 1901-1904: Magnetic Observations. London: Royal Society. Royds, C. W. R. (1903). Report the of Barrier sledge journey. Cambridge: Thomas Manning Archive, SPRI, MS/366/13/3; ER. Royds, C. W. R. (2001). The Diary of Lieutenant Charles W. R. Royds RN: expedition to the Antarctic 1901-1904. Braidwood, NSW: T. R. Royds. Scott, R. F. (n.d.). Objectives for Sledge Parties 1903. Cambridge: Thomas Manning Archive, SPRI, MS/366/13/85; ER. Webb, E. N. & Chree, C. (1925). Field Survey and Reduction of Magnetograph Curves. Analysis and Discussion of Magnetograph Curves Australasian Antarctic Expedition 1911-14 Scientific Reports Series B, Vol 1 Terrestrial Magnetism. Sydney: Government Printer. Webb, E. N. (1965). Magnetic Polar Journey 1912. Christchurch: Canterbury Museum Archive. Eric Norman Webb MS166. Webb, E. N. (1975). Interview with Eric Webb, Antarctic explorer [sound recording] / interviewer, Lennard Bickel.: Unpublished Oral History. National Library of Australia. Retrieved from http://nla.gov.au/nla.oh-vn1762284 Yelverton, D. E. (2000). Antarctica Unveiled. Boulder, Colorado: University Press of Colorado. Directory: Upload Upload -> 587 Return function, r i(X) r i(0) r i(1) r i(2) r i(3) 1 0 2 4 6 Thermal Station, I 2 0 1 5 6 3 0 3 5 6 10 Upload -> Department of science and humanities department of mathematics part-a questions and answers Upload -> The Case Against the nypd’s Quota-Driven ‘Broken Windows’ Policing What Is It? Upload -> For want of a nail Upload -> Traditional British values Upload -> Tv shows, Made for tv movies, Mini Series & Internet Programs Shot at Paramount Ranch Upload -> Ownership Models There are two different types of ownership models Upload -> Police Militarization Upload -> City of rising star regular meting thursday, july 14, 2016 Upload -> Township of winfield Download 4.64 Mb. Share with your friends:
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