South! - Ernest Shackleton (best short novels TXT) 📗
- Author: Ernest Shackleton
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Loose open ice, where the area of water exceeds that of ice. Generally drift-ice is within reach of the swell, and is a stage in the breaking down of pack-ice, the size of the floes being much smaller than in the latter. (Scoresby’s use of the term drift-ice for pieces of ice intermediate in size between floes and brash has, however, quite died out). The Antarctic or Arctic pack usually has a girdle or fringe of drift-ice.
BrashSmall fragments and roundish nodules; the wreck of other kinds of ice.
Bergy BitsPieces, about the size of a cottage, of glacier-ice or of hummocky pack washed clear of snow.
GrowlersStill smaller pieces of sea-ice than the above, greenish in colour, and barely showing above water-level.
CrackAny sort of fracture or rift in the sea-ice covering.
Lead or LaneWhere a crack opens out to such a width as to be navigable. In the Antarctic it is customary to speak of these as leads, even when frozen over to constitute areas of young ice.
PoolsAny enclosed water areas in the pack, where length and breadth are about equal.
MeteorologyBy L. D. A. Hussey, B. Sc., (Lond.), Capt. R.G.A.
The meteorological results of the Expedition, when properly worked out and correlated with those from other stations in the southern hemisphere, will be extremely valuable, both for their bearing on the science of meteorology in general, and for their practical and economic applications.
South America is, perhaps, more intimately concerned than any other country, but Australia, New Zealand, and South Africa are all affected by the weather conditions of the Antarctic. Researches are now being carried on which tend to show that the meteorology of the two hemispheres is more interdependent than was hitherto believed, so that a meteorological disturbance in one part of the world makes its presence felt, more or less remotely perhaps, all over the world.
It is evident, therefore, that a complete knowledge of the weather conditions in any part of the world, which it is understood carries with it the ability to make correct forecasts, can never be obtained unless the weather conditions in every other part are known. This makes the need for purely scientific Polar Expeditions so imperative, since our present knowledge of Arctic and Antarctic meteorology is very meagre, and to a certain extent unsystematic. What is wanted is a chain of observing stations well equipped with instruments and trained observers stretching across the Antarctic Continent. A series of exploring ships could supplement these observations with others made by them while cruising in the Antarctic Seas. It would pay to do this, even for the benefit accruing to farmers, sailors, and others who are so dependent on the weather.
As an instance of the value of a knowledge of Antarctic weather conditions, it may be mentioned that, as the result of observations and researches carried out at the South Orkneys—a group of sub-Antarctic islands at the entrance to the Weddell Sea—it has been found that a cold winter in that sea is a sure precursor of a drought over the maize and cereal bearing area of Argentina three and a half years later. To the farmers, the value of this knowledge so far in advance is enormous, and since England has some three hundred million pounds sterling invested in Argentine interests, Antarctic Expeditions have proved, and will prove, their worth even from a purely commercial point of view.
I have given just this one instance to satisfy those who question the utility of Polar Expeditions, but many more could be cited.
As soon as it was apparent that no landing could be made, and that we should have to spend a winter in the ship drifting round with the pack, instruments were set up and observations taken just as if we had been ashore.
A meteorological screen or box was erected on a platform over the stern, right away from the living quarters, and in it were placed the maximum and minimum thermometers, the recording barograph, and thermograph—an instrument which writes every variation of the temperature and pressure on a sheet of paper on a revolving drum—and the standard thermometer, a very carefully manufactured thermometer, with all its errors determined and tabulated. The other thermometers were all checked from this one. On top of the screen a Robinson’s anemometer was screwed. This consisted of an upright rod, to the top of which were pivoted four arms free to revolve in a plane at right angles to it. At the end of these arms hemispherical cups were screwed. These were caught by the wind and the arms revolved at a speed varying with the force of the wind. The speed of the wind could be read off on a dial below the arms.
In addition there was an instrument called a Dines anemometer which supplied interesting tracings of the force, duration, and direction of the wind. There was an added advantage in the fact that the drum on which these results were recorded was comfortably housed down below, so that one could sit in a comparatively warm room and follow all the varying phases of the blizzard which was raging without. The barometer used was of the Kew Standard pattern. When the ship was crushed, all the monthly records were saved, but the detailed tracings, which had been packed up in the hold, were lost. Though interesting they were not really essential. Continuous observations were made during the long drift on the floe and while on Elephant Island the temperature was taken at midday each day as long as the thermometers lasted. The mortality amongst these instruments, especially those which were tied to string and swung round, was very high.
A few extracts from the observations taken during 1915—the series for that year being practically complete—may be of interest. January was dull and overcast, only 7 percent of the observations recording a
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