this place these beds represent terrestrial conditions, there being an entire absence of marine fossils. This flora is characterized by numerous ferns, especially Gleicheniæ; by a remarkable cycad (Zamites archea); by numerous conifers, belonging to the genera Pinus, Sequoia, &c.; and by the absence of dicotyledons. The upper cretaceous beds are developed between Atanekerdluk and Atane. They comprise thick strata of coal, and the fossils are terrestrial; the marine being absent. The flora comprise cycads, ferns in abundance, Sequoia, and numerous dicotyledonous leaves. The great bulk of the strata on and around Disco Island are of Miocene age. Plants have been collected from three distinct horizons representing periods separated by considerable intervals of time. The lowest horizon occurs at Atanekerdluk. The beds are remarkably rich in impressions of plants, and in carbonized trunks of trees. These trunks are in places so abundant that the Greenlanders collect them for fuel. The second horizon contains beds of coal, and impressions of leaves, cones, seeds, &c., as also carbonized and silicified tree-stems at Netluarsuk, Ifsorisok, and Assakak. At Sinnifik and at Perilosok an upper Miocene flora occurs, represented by fragments belonging to such trees as Salix Platanus, Crataegus, Sequoia, Taxiles, and Populus.

INTRODUCTORY CHAPTER.

These localities are on or near 70° N.

39

Spitzbergen

These floras

also has yielded a rich Miocene flora. indicate a climate as warm as the temperate, or perhaps even the temperate parts of Europe at the present time. Professor Heer believes that extensive forests were spread over all the North Polar lands during the Miocene period. Dr. Hooker infers from the present remarkable distribution of the Arctic plants that they migrated across the Polar region at a time when the warmth was much greater than now. An examination of the plants of the Polar lands, discovered and undiscovered, present and past, would enable botanists to found their conclusions on a broader and safer basis than they can now. The work that has already been done is a strong inducement to continue the research and render this region one of the most interesting and instructive in the world.

Another branch of science which would be greatly advanced by Polar research is terrestrial magnetism. The magnetic needle, as is well known, points to the magnetic North, or Pole, which Pole lies considerably to the south of the earth's Pole. In 1830 Sir James Ross discovered it in 70° 5' 17" N., and 96° 46′ 45′′. It is also constantly shifting its position from E. to W. and from W. to E., within certain limits, and

See list of miocene flora and fauna given in the body of the present work.

probably on or near the same parallel of latitude. In 1663 it was due north of Paris: it then advanced westwardly till about 1819, when it returned eastwardly, in which direction it is still moving, and Bond supposes that the eastern limit will be reached in about 2140. There are so many resemblances and analogies between the secular and local distribution of the elements of terrestrial magnetism and heat that many persons are convinced that there is an intimate connection between them. The magnetic Pole lies near the region of greatest mean cold, and its course appears to be along the zone of lowest mean temperature. Auroras are believed to be essentially the results of magnetic disturbance, and originate, or at any rate are most abundant and energetic along a zone situated on and near the latitude of the magnetic Pole, which is probably that of greatest cold. It is inferred that no auroras are produced north of about 80°; in other words, that a person at the Pole would see the auroras on the southern sky. The alternate heating and cooling of the Polar area, together with the great difference of temperature between the zone of greatest cold and the tropic of the northern hemisphere, would seem an adequate and probable cause for the generation of magnetic currents and storms. The auroras are observed to occur in cycles of varying

INTRODUCTORY CHAPTER.

41

intensity and frequency, lasting about eleven years; and these variations seem to coincide with the variations in the number and importance of the spots on the sun, which also run through cycles of about eleven years. According to Mr. Meldrum the cyclones of the Indian Ocean also occur in eleven yearly cycles, during which their frequency and strength coincide with the condition of the solar spots. He also infers, from a careful examination of the meteorological reports of various places, that in the countries surrounding the Indian Ocean, such as Ceylon, Mauritius, Adelaide, &c., the rainfall periodicity corresponds with the cyclone periodicity; and that the years of maximum rainfall correspond with the years of maximum sun-spot frequency, while the years of minimum sun-spot frequency are those of minimum rainfall. These remarks suggest that the observation of the climatic and telluro-magnetic elements in Polar regions would lead to results of the highest scientific importance, which would also be of great practical benefit. This object alone should be a sufficient answer to those who want to know what use there may be in Polar research. The scientific man knows that no well-conducted inquiry is useless; and that the electric telegraph, the steam-engine, the galvanic battery, and numerous other inventions of unques

tionable practical importance originated in apparently useless inquiries.

The phenomena and distribution of Arctic ice are subjects worthy of investigation. It does not answer our purpose to detail the numerous observations made by Arctic voyagers. These observations indicate that the icebergs and ice-fields are loosened every summer, and sent drifting southward. These masses accumulate most where there is most land, and by their melting they transfer the cold of higher latitudes to these more southern lands, and thus reduce their mean temperature. This has the effect of throwing the zone of greatest cold towards the south, especially where the lands advance far north. Observations upon the thickness of ice found each winter or each year at several localities would enable us to define the zone of greatest cold, and also infer from the thickness of the ice whether the regions around the Pole are warmer than in about 75° N. What are the regions of perennial ice? for that there are such regions seems clear from the occurrence of sea ice in sheets formed of annual layers. These regions may be the true sources of the cold currents of the sea; while the warm currents have a temperature of 40° or 45° F., and flowing from the north, may arise from the area where the sea is freed every year from ice by the