THE NORTHERN v. SOUTHERN HEMISPHERE.

Nelson Evening Mail, Volume XIV, Issue 110, 9 May 1879, Page 4

THE NORTHERN v. SOUTHERN HEMISPHERE.

An article by Professor Merriman in v ppw fi menVnn \* nrn»l, the Popular Scientific Montfily, on the " Polar G'pfierp,'' cn n t«in« startling deduction* from rpppnt dippovriPß, of whirb. thp following is a s'immnry :— -The Profeppor sets rot by stating that thp ren?ro of pravify of ?he earth is thp centre of the sphere formed by tho purfare of the oceanf — making slight allowances for polar flattening, it ia a point fqually distant from the level of the sea on b!1 sides. Tn each hemisphere tbo sea level in the same latitude would be at the same distance from the centre, and whatever excess of visible land there is ia one half must be balanced by gome corresponding weight in the other half. And it is evident that (Ms counterpoising weight must, in fact, be land, supposing, as is almost Certainly the case, that the hemispheres are equally heavy according to bulk. It therefore follows to a mathematical demonstration that there is exactly the same weight of land projected above the wafer in both hemispheres. But the map of the world, as geographers have outlined i' t shows that there is apparently a vast preponderance of land oorth of the rqaator. Humboldt estimated that Asia stands' at the average height of 1150 feet above the sea; South America, 1130; North America, 750; Europe, 670, The average height of the whole — omitting Africa and Australasia, which are about es couch south as north of the equator — is 920 feet. There are in the northern hemisphere, 44,000,000 square miles known to geogrnphers) in the southern, about 1 6,000 .000-— little more than a third; 88 much — leaving a diffence of 28 000,000 square miles, averaging 920 feet high. But as there is the same visible excess of water on the southern side that there is of land on • the northern, and the depth of the sen is about the same, it follows that the weight of tbe» excess of submerged land in the northern hemisphere must be added to the 28,000,000 equare miles, doubling the height of it, end making ; it at least 1840 feet above the average l level of the southern continents and ' oceans' depths. What ia there gontb I of the equator to balance this ? We must have something, or the partb would not maintain its poise. There j must be something on the Bouthern side to balance the. orb and~ make '^the j water level possible. This balancing weight is estimated by Professor Merriman to lie oo thai, vast unexplored and incessible regioo, as large as North America, thai caps and surrounds the* southern pole. But supposing this 8,000,000 miles within the Antarctic circle to be land, it would still require over it "all 7 nn average thickness of two and a-half miles of solid ice to make the southern hemisphere equal the northern in weighf. This vast ioeberg Profeeeor : Merrimaa believes to exist. The voyages of explorers thereaway seem to 'confirm tbhf hypothesis. iThey have not been abld' to penetrate the high and formidable barrier which maeka this desolate region. No. sign of animal life or vegitatiori is thare, while within the Artie circle at the north there are numerous settlements and whole races of men. In the north, sledges have penetrated within 600 miles of the -pole; ia the south no man ever ventured r wttb'in 1500 miles. What causes this great difference ? The explanation is plain. Owing to ii s eccentric movement around the sun oar northern summer is some, eight days longer ibanour winter* i while T in the south the winter is eight days longer tbaff- the aiftnbJer. ThTs sixteen days matteirtdfcb/ difference, which is emphasized by the additional factthat during the long southern Winter the earth j •8 farthest from the sun. Tbua year after year for, a long period, there hag been I a steady accumulation of ice material about the south pole, adding weight to that hemisphere. TheD, as thiff'weignt of ice* jr/creased, the earth's centre of ! gravity has gradually moved to the south, and -the ; waters fluent and qbediebt'tb "graviiation, have slowly gathered in io southern eeae, covering j the lowlands of the south. At the name time ihie transfer of weight from the north hns'drawn the waters away from the A rtic L regions, and left the SCftbare - and shoals to project and ! become habitable. Bnt this state of things is not always tit go on. The north is not always to bask in the longest summer. The earth, >ib addition to its diurnal j and annual revolutions, has a slow wabbling of its axes in'therbeavens. It is j precisely as when one touches the rim j of a lop io rapid motion;; the upper end of the stem describes a small circ}e. Bo the mighty sod lays hold of the protnberant rim of the great terrestrial top, and it begins ito oscillate in the long period of 21,000 . years, that ia to say, on December 21, 1248, the earth, made its nearest approach to the sun; and it will approach equally near in 10,500 years from that time, or in the year 11,748. on July 21. In the period comprising the first case our iiorthern winters are short and mild, ■od oar summers long aad sunny. Daring the period of " which the year 11,748 will be the middle, our winters will be severe, and onr summers sbort, The northern hemisphere is now losing; its great summer. In about 10,000 years it will be in the midat of its great and terrible winter. Then the southern bemiapbere will be full of sunlight ''and prolonged warmth. QNow let u§ see what would result frofflihU. The melting of « mile in

thickness of the ice-crjpola of the south pole would raiee the sea-level i.t the north pole 300 feet, ftfc London 200 feet, and at New York 200 feer. If <uo wbolo ice-cupola were removed and an fquaf quantity deposited at the north pole, thpre would be a deepening of the sea at ihe Arctic circle of 1500 feet ; at Npw York of considerably more than 10,000 feet. Thus it is seen that, fis certainly as terrestrial revolutions continue, in the course of 10,000 years there must come an entire reversal of polar conditions. The southern waters must be drained off to make the oceans of an opposite hemisphere. New lands, enriched with the sediment of a hundred centime?, will rise up to ; extend the borders of the old south continents, and islands joining together will expand into mainlands. At the same time the northern continents roust be in a great part submerged and their summits and ranges become the bleak islands and the rold headlands of a femp.~Btuoua ocean. Central Asia, with its broad table-lands, may still retain the name of a continent, but beyond a few outlying islands tber© will be no Europe and but little of North Amerioa left. The Atlantic waters will stand 500 feet over Lake Superior, and will wash the base of the Rocky Mountains in all their length. A new Gulf stream may again, as it must often j have done before, flow up the Valley of the Mississippi, returning the deltas to the prairies and making the beds of the garden of the» world. These are no idle or impossible fancies. Not only are they results of rigorous calculation, but they accord perfectly with 'the unmistakable evidences which the ocean has left on all our lanJ of its recent work and presence.