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procedure, which requires a scrupulous examination of the detail, together with a wide survey of generality, it exchanges constantly the small circle of special research and the wide field of general ization. Must not such a change between restriction and expansion be most helpful? It is a fact that the type of the learned specialist who is almost a stranger to the problems beyond the limits of his own work is in no field so rare, if not so totally absent, as in geography. The broadest-minded people of the fine staff of German scientists, the most alive to the interests of the world about them, are met with among the professors of geography. Geography forces its apostles to keep constantly apace with all the progress around them.

In

no other field of study would the neglect of almost any question of the day, scientific or not, prove more fatal than here. The introduction of the study of geography into the universities, therefore, is a powerful ally to keep the students from becoming narrow in their views, from looking no further than the small circle within which the axis of their own special interests rotates. It will make them tolerant by teaching them to understand different conditions, and to make allowance for different consequences arising from these different conditions. It will make them wise and successful in contact with political questions, because they will not expect nor exact from foreign nations more than they can afford, according to their actual state and circumstances.

UTILITY OF GEOGRAPHY

Geography, more than almost any other science, has the power to enrich the lives of those who devote themselves to its study. The botanist may teach you the secrets of the life of trees and plants, the zoologist introduce you into the interesting ways and habits of many a little fellow-creature, the geologist

open your eyes for the charms of tracing the history of the soil which you tread, but none gives you such an entire and satisfactory feeling of nature as geography. It is the entirety of the impression upon which stress ought to be laid. The natural disposition of the average mind goes to the whole. Even a good botanist or other scientist will be specially interested only in part of what surrounds him, be it plants or animals or stones, sometimes even only in a certain class or family of them. Geography teaches you to enjoy nature as a whole. It tells you why the soft lines of this mountain range, covered with dark firs, slope so gently down to the valley, while yonder ice-capped summits tower up steep and bold to the sky. It shows you why here waving cornfields reward the farmer's labor, and why another region seems to be one enormous meadow.

Geography will contribute, too, to improve the character and adorn the life of the student. It will make him feel familiar and at home on almost every spot of the earth; nowhere will he stand criticising and complaining of what is different from his native place, but appreciate the differences of nationality, and instead of repining for what cannot be changed, come home enriched by the touch of many a string in his heart which would never have resounded under other circumstances. In the character of the German nation we see this side highly developed, too highly even from certain points of view. The readiness with which the German adopts foreign customs when he goes abroad, as well as when they are brought to him, the facility with which as an immigrant he accommodates himself to the conditions of his new home is in great measure due to his highly developed feeling of geographic equity. A reasonable portion of it added to national character would be an improvement for many races.

Political geography, especially, must

not be forgotten when we deal with the advantages of geography. Much information of high value is offered through it to the student. Economic and social problems, questions of government and constitution, which when treated in an abstract and theoretical way will often fall short of the understanding, as well as of the interest of young brains, find here wonderful material for exemplification, object-lessons in public life, poli

tics, economy, and sociology. Enormous treasures lie hidden here, waiting only for the right digger to discover them. In a country where interest in public. affairs is so strong as in this great Republic, this duty of the schools should be cherished most conscientiously. Geography should be given the place which it deserves, not only in elementary instruction, but also in all high schools and universities.

THE DRIFT

A

OF FLOATING BOTTLES IN THE PACIFIC OCEAN

BY JAMES PAGE, U. S. HYDROGRAPHIC OFFICE

MONG the various investigations carried on by the U. S. Hydrographic Office, there is one which has always excited greater or less popular interest, owing probably to the fact that it lies within the power of any one who is at sea, and who is likewise gifted with a reasonable amount of curiosity and the leisure time to gratify it, to contribute toward the end in view. This particular field of research is the investigation of the surface currents of the sea by means of the knowledge obtained through the drift of floating bottles, or, as it is familiarly known, the drift of bottle papers. The apparatus required is not extensive. The date, the latitude, and the longitude of the vessel at any given time are written upon a piece of paper; this paper is then placed in an empty bottle of whatever character is nearest to hand; the bottle is then corked and sealed and cast into the sea. After the lapse of time, sometimes of years, certain of these bottles find their way to the coasts of the adjacent continents or islands, and the papers contained in them ultimately reach the U. S. Hydrographic Office.

The office assists in the investigation to the extent of furnishing the pieces of paper. These are prepared in blocks, and are distributed free of charge to the masters of vessels who promise to undertake the task of casting them adrift-a promise which, the results prove, is rarely violated. The paper is printed in seven languages in order that it may be readily understood, no matter upon what coast it ultimately lands. The first part, which is to be filled in by the person who casts it adrift, contains a space for the name of that person, for the name of the vessel, the date, the latitude, and the longitude; the second part, which is to be filled in by the discoverer of the bottle, a space for the name of the finder, the date, and the locality in which it is found. At the bottom of the paper the finder is instructed, in seven languages, to return the paper to the U. S. Hydrographic Office.

Several hundred of these papers find their way back each year, the great majority of those which are returned having been cast adrift in the Atlantic Ocean, and charts have from year to year appeared showing the drift of bot

tles in that ocean. These charts all unite in showing a steady easterly drift in the temperate latitudes of both the North and the South Atlantic, and an equally steady westerly drift in the tropical latitudes, the generalized current system of either ocean thus consisting of a vast eddy about some central point, the direction of the circulation being anti-cyclonic in either hemisphere i. e., with the diurnal motion of the sun, as observed in that hemisphere, just as in the case of the prevailing winds.

At

Taken collectively, the lines of drift of floating bottles in the Pacific again show, precisely as in the case of the Atlantic Ocean, that the general direction of the drift is eastward in the higher latitudes, westward in the lower. least this is so for the North Pacific. For the South Pacific evidence of the eastward motion of the extratropical waters is lacking. None of the drifts reveal the existence of the equatorial counter-current flowing eastward between the westward-moving equatorial currents of the southern and northern hemispheres. The average velocity of the easterly drifts is 4.4 miles per day, of the westerly drift 10 miles per day, or more than twice as great, which is again in accordance with the results for the Atlantic Ocean. The highest velocity attained was that of a bottle thrown overboard from the steamer Warrimoo January 23, 1897, in latitude 4° N., 168° W., and found March 6, 1897, on one of the Gilbert Islands, having drifted 1,100 miles in 42 days, or at an average rate of 26 miles per day. None of these velocities makes any allowance for the time during which the bottle may have lain undiscovered on the beach. The longest drift was that of a bottle which was thrown overboard near Cape Horn June 18, 1896, and found near Cape York, on the northern coast of Queensland, Australia, after the lapse of nearly three years. The shortest practicable route which it could have pursued meas

ures 10, 100 miles in length, or nearly two-thirds of the total distance around the earth in the latitude of its path, giving an average velocity of 10.1 miles per day. The actual distance traversed was probably much greater than this.

My main object in directing attention to these drifts is to suggest the idea that they illustrate an apparent paradox. The bottles themselves float upon the surface, but if I were asked whether the lines drawn upon a chart to show their course represented the surface currents of the sea, the currents with which the navigator has to deal, I should say emphatically no. The actual surface currents present no such uniformity, either in direction or velocity. As an example of this, take the currents actually observed in the five-degree square of the North Atlantic Ocean bounded by the parallels 35 to 40 degrees north and the meridians 65 to 70 degrees west (off the coast from Hatteras to Sandy Hook), in the heart, therefore, of what is ordinarily known as the Gulf Stream, concerning which the popular impression is that it flows along steadily like a mighty river. For any given month, say September, the currents actually observed within this square were as follows:

Setting northeast, 32 per cent of the whole number of observations ranging from 6 to 70 miles in 24 hours.

Setting southeast, 23 per cent of the whole number of observations ranging from 8 to 65 miles in 24 hours.

Setting southwest, 27 per cent of the whole number of observations ranging from 6 to 76 miles in 24 hours.

Setting northwest, 18 per cent of the whole number of observations ranging from 9 to 63 miles in 24 hours.

Evidently here there is none of the uniformity presented by the drifts and which the mind ordinarily associates with the Gulf Stream.

To get at the true meaning of these lines of drift beyond the fact that they represent the resultant of the traverse

line pursued by the bottle in its journey, it is necessary to go back to the motive power which gives rise to the surface. currents of the sea, viz., the winds. A perfectly steady wind acting continuously on the surface of the sea will, through friction, give rise to a movement of the surface waters in the same direction as the wind itself. If the latter continues for a sufficient length of time the impulse, first felt only at the surface, will gradually communicate itself downward, owing to the viscosity of the water, and the lower strata to a successively greater and greater depth will thus partake of the movement until it is finally shared by the whole mass, the velocity of the motion diminishing as the depth increases. The rate, however, at which this motion is communicated to the depths of the ocean is exceedingly slow. It has, for instance, been estimated that in a depth of 2,000 fathoms a surface current of given velocity would require a period of 200,000 years to transmit its due proportion of this velocity to a point halfway toward the bottom. Similarly, when once established, these submarine currents exhibit a corresponding reluctance to undergo any variation in direction or intensity.*

Perfectly steady winds, however, do not exist, even in the region of the trades. The winds are constantly

* Zöpprits, Annalen d. Hydrographie, 1878.

changing, and the surface currents change with them. The lower strata of the ocean, however, are insensible to these changes, and at a considerable distance below the surface the waters of the ocean have probably a slow but perfectly uniform motion, the direction of the motion probably agreeing closely with that of the resultant surface winds.

We have, therefore, in the body of the sea two distinct sets of currents; first, those at the immediate surface, which move practically at the obedience of the surface winds, sometimes in one direction, sometimes in another: second, those of the lower strata, which are constant in direction and velocity and represent the aggregate effect of the winds that have blown for ages past, the sea in this respect furnishing a close analogy to the atmosphere, the motion of the lower strata of which is constantly disturbed, while that of the higher strata, as shown by the motion of the cirrus clouds, is comparatively uniform.

It is the motion of these lower strata, as I take it, that the uniform paths pursued by these drifting bottles to some extent represent, and it is the evidence contained in them that should be studied in investigations dealing with the currents of the ocean in their entirety, rather than the evidence obtained from any given set of current measurements made at or near the surface and for some given point.

THE BRITISH ANTARCTIC EXPEDITION

T

HEDiscovery, carrying the British National Antarctic expedition, is now well on her way to South Polar regions. The proposed work of the party has been carefully outlined by the presidents of the Royal Society and of the Royal Geographical Society in their instructions to Captain Scott and

to Dr. George Murray, the scientific director. The instructions to the commander are as follows:

1. The Royal Society and the Royal Geographical Society, with the assistance of His Majesty's Government, have fitted out an expedition for scientific discovery and exploration in the Antarctic.

regions, and have entrusted you with the command.

2. The objects of the expedition are: (a) to determine, as far as possible, the nature, condition, and extent of that portion of the South Polar lands which is included in the scope of your expedition, and (b) to make a magnetic survey in the southern regions to the south of the 40th parallel, and to carry on meteorological, oceanographic, geological, biological, and physical investigations and researches. Neither of these objects is

to be sacrificed to the other.

3. The scientific work of the executive officers of the ship will be under your immediate control, and will include magnetic and meteorological observations, astronomical observations, surveying and charting, and sounding operations.

4. Associated with you, but under your command, there will be a civilian scientific staff, with a director at their head. A copy of his instructions accompanies these instructions to you.

5. In all questions connected with the scientific conduct of the expedition you will, as a matter of course, consider the director as your colleague, and on all these matters you will observe such consideration in respect to his wishes and suggestions as may be consistent with a due regard to the instructions under which you are acting, to the safe naviigation of the ship, and to the comfort, health, discipline, and efficiency of all under your command. Those friendly relations and unreserved communications should be maintained between you which will tend so materially to the success of an expedition from which so many important results are looked for.

6. As the scientific objects of the expedition are manifold, some of them will come under the immediate supervision of the director and his staff; others will depend for their success on the joint coöperation of the naval and civil elements, while some will demand the undivided attention of yourself and

your officers. Upon the harmonious working and hearty coöperation of all must depend the result of the expedition as a whole.

7. The expedition will be supplied with a complete set of magnetic instruments, both for observations at sea and on shore. Instructions for their use have been drawn up by Captain Creak, R. N., and yourself and three of your officers have gone through a course of instruction at Deptford with Captain Creak and at Kew Observatory. The magnetic observatory on board the Discovery has been carefully constructed with a view to securing it from any proximity to steel or iron, and this has involvel considerable expense and some sacrifice in other respects. We therefore impress upon you that the greatest importance is attached to the series of magnetic observations to be taken under your superintendence, and we desire. that you will spare no pains to ensure their accuracy and continuity. The base station for your magnetic work will be at Melbourne or at Christchurch, in New Zealand. A secondary base station is to be established by you, if possible, in Victoria Land. You should endeavor to carry the magnetic survey from the Cape to your primary base station, south of the 40th parallel, and from the same station across the Pacific to the meridian of Greenwich. It is also desired that you should observe along the tracks of Ross, in order to ascertain the magnetic changes that have taken place in the interval between the two voyages.

8. Geographical discovery and scientific exploration by sea and land should be conducted in two quadrants of the four into which the Antarctic regions are divided for convenience of reference, namely, the Victoria and Ross quadrants. It is desired that the extent of land should be ascertained by following the coast lines, that the depth and nature of the ice cap should be investigated, as well as the nature of the vol

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