In dealing with continental areas Dr. Rohrbach draws contour-lines on a map parallel to the coast-line at certain chosen intervals, and measures the areas contained with a planimeter. If great accuracy be desired, the lines must be traced on a map in which there is no distortion, and then transferred for measurement to an equal-area map, but in a first assay, to demonstrate the applicability of the method and the value of its results, Dr. Rohrbach considered Bonne's projection sufficiently accurate for tracing the lines as well as for measurement. A map of the world and another of Europe are appended to the article, on which the contour lines are drawn, and the coast-distance of the areas between them denoted by different colours. The relative conditions of the continents are also shown, both by rectangles of which the bases are proportional to the areas, and the altitudes to the mean coast-distances, and also by curves-chorigraphic, as Dr. Rohrbach calls them-where the ordinates represent the coast-distances corresponding to the areas indicated by the abscissæ. Tables are given showing the areas lying beyond different distances from the coast in the various continents, both in square kilomètres and in percentages. The following shows the mean coast-distances : Europe, 208 miles. Africa, 417 miles. Australia, 214 miles. North America, 292 miles. The five Continents, 381 miles. As a measure of the accessibility of continents from the coast, Dr. Rohrbach proposes the quotient obtained by dividing the mean distance in a circle, or in a calotte, of equal area by the actual mean distance, and gives the numbers in the latter case, but the result is scarcely satisfactory. As he himself points out, Eurasia appears to greater advantage than Europe, because the mean distance in the calotte is calculated as though sea instead of land lay to the east, and thus the quotient is increased. It is also startling to find North America represented by a higher figure than Europe, and the five continents by a number more than twice as great. It is easy to see that these discrepancies arise because the numbers represent only the advantage each continent derives from its actual shape compared with its accessibility if formed into a calotte, and do not indicate the relative accessibility of the continents. A more correct idea is obtained by taking the mean coast-distance (1416 miles) in a calotte of area equal to that of the five continents, or the actual mean distance (381 miles), as unity. In the latter case the numbers are as follows: Dr. Rohrbach claims that his method is superior to those before employed, because the mean coast distance is a quantity admitting of simple definition, and not deduced by any artificial means from the geometrical forms. Its value also is easily reckoned, and can be worked out to any desired degree of accuracy, maps of various scales being employed according to the extent and configuration of the countries under examination. In almost all other methods the length of the coastline has been used, the estimation of which leaves much room for speculation, causing great uncertainty in the results. In the present method this quantity is not needed, and yet the meanderings of the coast-line exercise their due influence on the curvature of the contour lines, as may be clearly seen on the map of Europe already alluded to. And not only is the method applicable to purely morphological investigations, but charts may also be constructed, showing the relative conditions of the various parts of a country with regard to means of communication. Thus, an ice-bound coast may be treated as an inland boundary, and, where a chain of mountains intervenes, the contour-lines may be drawn so that their normals run to the sea past the extremities of the chain, or converge to the passes. Navigable rivers, railways, etc., may also be taken into account, and also the elevation, etc., charts being constructed to show the work required to transport a unit weight of goods, say a hundredweight, from the coast. Each contour-line in such charts will pass through all places to which the labour of transport is the same, and will therefore resemble an isobar or isotherm. Tidal Prediction.--Professor G. H. Darwin, in the Bakerian Lecture delivered on January 29th, showed how tables may be drawn up from which the tides at a port may be rapidly computed for any day. The information supplied by the Admiralty is very rough, and makes no allowance for the diurnal tide due to the moon's declination, and there is no arithmetical method of computation employed which does not involve much labour and expense. The variation in the height of the water depends principally on the mean longitudes of the moon and sun, and, in a less degree, on the longitudes of the lunar perigee and node. Professor Darwin's tables, then, give the intervals after the moon's transit and the heights of high and low water, with corrections depending on the longitude of the moon's node and her parallax, calculated for every twenty minutes of the moon's transit and for about every ten days in the year. To test the accuracy of these tables the port of Aden was chosen, its tides being very complex and apparently irregular, and the results worked out by Mr. J. W. F. Allnutt were compared with the predictions of the Indian Government, or with the data given by actual observation. In the latter case the probable error was seven minutes in time and 14 inches in the height of the water.-Nature, Feb. 5th, 1891. Dr. Nansen's Arctic Expedition.-As misconception prevails and erroneous statements are being circulated with reference to Dr. Nansen's proposed Arctic expedition, it may be advisable to give the facts as to what has been done and arranged up to date. This we are able to do at first hand. Dr. Nansen's desire is to leave Norway in February 1892, but it is doubtful whether the special vessel which is being built will be ready by that time. Outside of Norway no money has been contributed. The expedition is purely Norwegian, and will remain so. The Norwegian Government contributes 200,000 kroner; King Oscar, 20,000; twelve private individuals (all Norwegians, except one Englishman, who has lived in Christiania for many years), 90,000: in all, 310,000 kroner, equal to £17,210. This sum, Dr. Nansen believes, will be sufficient. The ship, of course, is being specially constructed for the peculiar conditions that exist between the New Siberian Islands and the Pole. Dr. Nansen will be accompanied by probably not more than eight young men, all as stalwart and strong in physique as himself, and all equally confident of success. It may be of interest to state that Messrs. Longmans and Co. will shortly publish a work on the New Siberian Islands, the real starting-point of the expedition, by Baron von Toll, who, as a member of a recent Russian expedition, spent a considerable time in their exploration.-Times, 6th March. COMMERCIAL GEOGRAPHY. Proposed New Railways in Scotland. -At a recent meeting of the Glasgow Philosophical Society Mr. John Struthers submitted a paper dealing with a proposed new railway in Scotland. Beginning with the suggestion that the Glasgow and South-Western Railway-negotiations for amalgamation with the North British Railway being now broken off-ought to join the Highland and Great North of Scotland Companies, he proceeded to show how this could best be done by the construction of but comparatively short lengths of new lines. The new railway would leave the Glasgow and Paisley joint line at a point between Hillington and Arkleston, cross the level strath traversed by the river Cart, and ascend by an easy gradient to a spot behind Erskine House, where the highest level in this portion of the line would be attained. It would then cross the Clyde by means of a high-level bridge, and, proceeding through the Vale of Leven, would skirt the west side of Loch Lomond, where it would join the West Highland Railway, nearly 40 miles of which could be utilised, bringing the line to within a few miles of Loch Ericht. Leaving the West Highland system it would skirt the loch, and join the main line of the Highland Railway at Dalwhinnie, from which two branches would diverge, one running east and joining the Great North of Scotland system in Deeside, the other striking west and having its terminus at "The Narrows," opposite Skye. Should this proposal be carried out, it would result in binding together three isolated systems, and represent a capital of £24,000,000, with a mileage of 1100 miles. It is also proposed to construct a short line from a point between Georgemas Junction and Thurso to Gills Bay on the Pentland Firth. A new harbour is projected at Gills Bay, which the mail and passenger boats from Orkney could reach in a shorter time and with much more convenience than their present landingplace in Scrabster Roads. An alternative proposal makes Wick the departure point of this line. The Great North of Scotland Company have been approached with a view to the construction of a new line joining Wick and Helmsdale (both stations on the Highland Railway) and proceeding along the coast by Dunbeath and Lybster. Custom Duties in the Congo State.--At the Conference held in Brussels, in November and December of last year, it was decided, on the proposal of France, that the Powers holding territory in the basin of the Congo, viz., France, Portugal, and the Congo State, should make an agreement among themselves with respect to the duties to be levied. The modifications resulting from this agreement have been promulgated in the Bulletin Officiel of February, and will come into force on September 1st at the latest. Patent rights on ivory are suppressed: an export duty of 10 per cent. ad valorem is to be levied on ivory bought below Stanley Pool and in the region of the Upper Congo and its tributaries as far as they are navigable, within a distance of 50 kilomètres (31 miles) from these rivers; and a duty of 25 per cent. on ivory bought in any other part of the State. The value is assessed as follow ;-For pieces of ivory, teeth, etc., 10 francs per kilo.; for tusks weighing less than 6 kilos., 16 francs per kilo; and for tusks over that weight, 21 francs per kilo. This assessment will be periodically revised in accordance with the state of the market. These duties are instituted for a period of ten years, and during the same time caoutchouc will be subject to an export duty of 10 per cent. ad valorem. On the other hand, personal and direct taxes will be reduced to one-third for the first five years and to one-half for the remaining five. According to the Revue Française an import duty of 10 per cent. will be levied on fire-arms, powder and munitions of war, and salt, and of 6 per cent. on all other goods. Material for railways will be for the present exempt, and travellers' and missionaries' luggage, instruments, etc., will be admitted free. The Commerce of Japan.-The foreign commerce of this country amounted in 1889 to £22,694,079, of which £11,676,784 represents the exports, and £11,017,295, the imports. Compared with the preceding year these figures show an increase in the total commerce of over £833,000. The custom-house returns show also an excess of importation of specie and bullion over exportation amounting to £1,497,453. Yokohama has far the largest share in the commerce, and Kôbé takes the second place, the value of the goods passing through these ports being nine-tenths of the total. Great Britain and her colonies have by far the largest share in the foreign trade, the value being £9,249,755. The United States follow with £5,237,674, and then, far behind, France and China. A comparison with the figures of 1888 shows that Great Britain has lost trade to the value of £500,000, while the United States have gained an equal amount. It is proposed to construct a jetty at Yokohama, and to improve the harbours of Tokio and Nagasaki.—Bull. Consulaire Français, August 1890. The Siberian Railway.- The Boll. della Soc. Geog. Italiana has learnt from Russian sources that this railway, so often mentioned in these pages, is actually to be commenced in the spring. A technical commission, appointed to determine the route, and to decide whether the line should be continuous, or only connect the navigable rivers, has given its decision in favour of a continuous line, running from Ufa through Slatoust, Omsk, Krasnoiarsk, Nijni Udinsk, and Irkutsk, to the Amur, which river and its tributary, the Ussuri, it will follow, and thus reach Grafskaia and Vladivostok. Its total length will be about 4900 miles, and its cost about 54 million pounds sterling. Of the three sections into which the line may be divided, the first, from Slatoust to Tomsk, will cross a flat country comparatively well peopled, and, with the assistance of a branch to the region of the Altai and an augmentation of the traffic along the Ob and the Irtish, may soon pay its working expenses. The second section, from Tomsk to Irkutsk, does not promise such immediate advantages, but it traverses the auriferous region of Siberia. The last section, running through a thinly populated country with an inhospitable climate, will demand a large outlay, both for construction and working, and will be a constant source of expense for a long time to come. stations will be about 31 miles apart, and communication across the broader rivers will be effected by means of steamboats. The Times, February 14th, states that the Samara-Ufa line is already extended to Slatoust, and will be continued to the gold-mining town of Miask on the eastern side of the Urals, so that only 4785 miles of railway have to be constructed. It also gives the more moderate sum of £36,765,000 as the cost of the undertaking, which, by the use of pontoons and steam ferries in lieu of permanent bridges, may be reduced to about 35 millions. The The Kashmir Railway. The establishment of railway communication between Kashmir and India is of the greatest importance from strategical and commercial points of view. It is essential for the defence of India that rapid means of transport should exist to a part of the empire from which easy passes lead across the frontier. Again, the abundant crops of Kashmir can be carried down to the Punjab by rail at half the present cost, while, when famine visits this usually productive valley, as it did in the years 1877 and 1878, carrying off two-fifths or more of the inhabitants, it will be possible to render assistance to the sufferers. To tourists and residents in India cheap means of access to a lovely valley and an invigorating climate will be a great boon. Four routes into Kashmir, known respectively as the Banihál, the Punch, the Punjar, and the Abbottabad, have been carefully surveyed by Major-General de Bourdel, and of these the Punjar has been selected for the line as possessing the greatest combined advantages with respect to facility of construction and strategical considerations. Leaving the North-Western Railway near Rawal Pindi, this route runs through Punjar, Kohala, and Baramula, to Srinagar, a distance of 210 miles, of which 78 miles are within British territory. The cost of construction is estimated at two and a quarter to two and a half millions sterling, and will be borrowed under guarantees from the India and Kashmir Governments.-The Times, February 12th, 1891. The New Mail Route to China and Australia.-Sir G. Baden-Powell read an address on this subject before the London Chamber of Commerce (Journal, February 10th, 1891). It is proposed that the new line of steamers shall run from some port in the south of England, and that at Halifax connection shall be made with steamers to the West Indies, thus bringing Jamaica within eleven days' sail from Plymouth. In the transit from England to Chicago or St. Paul twenty-six or thirty hours will be saved as compared with the New York route. The main feature of the new route is, however, the through-traffic across the Pacific. The distances to be run are :-3000 miles across the Atlantic; 3500 across Canada; and then 4500 to Japan, or 6500 to Australia. Thus, more than a quarter of the whole distance to Australia can be traversed by express trains, and the ocean distances are not too great for a high speed in steamers. As the Atlantic can be crossed in five days, and Canada, by train, in the same time, a traveller will find himself starting on his voyage across the Pacific ten days after leaving England. The steamers run alongside the railway jetties at Halifax and Vancouver, and no delay is caused by coaling or transferring cargo. The mail contract provides that mail matter shall be carried once a month from Halifax to Hongkong within 684 hours in summer, and 732 in winter. In view of the increasing trade between Canada and countries lying beyond the Pacific, as well as of the large trade across the Atlantic, almost equalling in value that with the other countries of America, the establishment of this new line of communication must be looked upon as a most important event. It will also form a new link with our American colony, and provide an alternative route to the Australian colonies, should a war break out, and the Suez Canal be closed to British vessels. Even if the latter route should be open, merchantmen would run less risk from the enemy in crossing the open ocean, and no danger from rocky shores. Early this spring three splendid steamers will be on the Pacific, carrying the Chinese and Japanese mails, and though the Atlantic and Australian steamers have not yet been provided for, it is well known that responsible financial houses in London are ready to take up the scheme. The Canadian Government has made the handsome offer of a subsidy of £150,000 a year, and other countries will, no doubt, furnish assistance. MISCELLANEOUS. Mr. Frank Beddard, F.R.S.E., Prosector in the Zoological Gardens, London, has an excellent paper in Part II. vol. x, of the Proceedings of the Royal Physical Society on the Geographical Distribution of Earthworms. The paper is illustrated by two maps. The area surveyed in Burma during the past year was, according to the Administration Report, 31,680 square miles, including nearly 9620 miles on the Siamese frontier. 550 square miles were surveyed in Kyaukse by a cadastral party, and 81,000 acres of State lands in Upper Burma by local surveyors. M. Th. Tchernysheff, a geologist, accompanied by Professor Backlund, a mining engineer, and a botanist, has explored the tundras of North-East Russia, collecting valuable geological and orographical data and mapping-out about 25,000 square miles of an almost unknown region.-Nature, February 26, 1891. |