THEORY 
 
 ■6/ 
 
 OF THK 
 
 GULF STREAM, 
 
 SAMUEL HOLLINGSWORTH. 
 
 PHI LAD ELPHIA : 
 QORBDTT & CLARK80N PRINTERS, NO. 142 CHESTNUT STREET, ABOVE SIXTH. 
 
 1856. 
 
THEORY 
 
 OP THS 
 
 GULF STREA 
 
 EXPLAINED CHIEFLY THROUGH THE AGENCY OF 
 
 ^^'1 
 
 ffllar ®$at, 
 
 BY 
 
 SAMUEL HOLLINGSWORTH. 
 
 PHIL AD ELPHIA : 
 GORBDTT & CLAEKSON PKIHTERS, NO. 142 CHESTNUT STREET, ABOVE SIXTH. 
 
 1856. 
 
THE GULF STREAM. 
 
 Two very interesting lectures have recently been delivered 
 before the American Geographical and Statistical Society, by 
 Professor Bache and Lieut. Bent, U. S. N., the former upon 
 the Atlantic Gulf Stream, and the latter upon the Equatorial 
 Stream of the Pacific Ocean. The following extracts are 
 taken from the New York Herald, as reported 19th and 25th 
 of January last ; they are chiefly portions which relate to the 
 theory of these great currents ; for the statistical parts, and 
 other very interesting information, we refer to the lectures as 
 fully reported. 
 
 " The great part ^^hich the heat of the sun plays in disturbing the equili- 
 brium of the surface of our globe is well understood. AVherever he shines 
 upon the surface, the air resting upon it is set in motion, so that the circle 
 of the sun's illumination as it advances over the earth is a circle of 
 disturbance. 
 
 These currents of air carry the waters forward with them from east to 
 west, and when they meet the land great currents are produced, and taking 
 their direction from the land cai-ry the waters of the equatorial regions to 
 the north and south temperate seas, to be returned in those great 
 systems of circulation, some of which have long been knov/n to navigators 
 and geographers, and others of which remain yet imperfectly developed 
 {Carte Tiieoinale des Globe, par H. Nicolet — Project Dierne Carte des 
 Coiira.nt Mains, par M. Duperry : Library Smithsonian Institute. Two 
 of the most important of these — one of the North Atlantic and the other 
 of the North Pacific — -will form the subjects to be brought before you on 
 successive evenings, the one the American Gulf Stream, and the other the 
 Asiatic Stream — the first making, as is most probable, the circuit of the 
 Gulf of Mexico, its name indicating the view of Geograi)hers as to its 
 origin, issuing through the Straits of Florida, gradually leaving our coast, 
 
-i 
 
 and seeking that of Euvope, the main stream to return by a counter 
 current to the tropical regions in which it was first produced, the branches 
 recognizable in the Northern Seas of both America and Europe. The 
 second, as traced by Lieut. Bent, from the notes of our Jai)an Expedition 
 under Commodore Perry, deflected to the north by the shores of Formosa, 
 passing along the coast to the northward and eastward, and leaving it 
 at the projecting portion of the Coast of Japan, as our stream does the 
 Coast of North Carolina at Hatteras. 
 
 The first delineation of wdiich I have any knowledge, though it is 
 altogether probable that there were attempts made to show difl'ercut parts 
 of it at an earlier date, was that made by Dr. Franklin, in 1769-70, from 
 the information communicated by Captain Folger, of Nantucket, com- 
 manding a whaling vessel from that port. The details are so interesting, 
 that I insert it as a remarkable instance of practical sagacity on the part 
 of the fisherman and the philosopher : — 
 
 " Vessels are sometimes retarded and sometimes forwarded in their 
 voyages, by currents at sea, which are often not perceived. About the 
 year 1769-70, there was an application made to the Board of Customs at 
 Boston, to the Lords of the Treasury in London, complaining that the 
 packets between Falmouth and New York, were generally a fortnight 
 longer in their passages than merchant ships from London to Rhode 
 Island, and proposing, instead of New York, that for the future they should 
 be ordered to Newport. Being then concerned in the management of the 
 American Post Office, I happened to be consulted on the occasion : and 
 it appearing strange to me that there should be such a difference between 
 two places scarce a day's run assunder, especially when the merchant 
 ships are generally deeper laden, and more weakly manned than the 
 packets, and had from London the whole length of the river and channel 
 to run before they left the land of England, while the packets had only 
 to go from Falmouth, I could not but think the fact misunderstood or 
 misrepresented. There happened then to be in London a Nantucket sea 
 captain of my acquaintance, to w^hom I communicated the affair. He 
 told me he believed the fact to be true ; but the difference was owing to 
 this, that the Rhode Island captains were acquainted with the Grulf 
 Stream, which those of the English packets were not. ' We are well 
 acquainted with that stream,' said he, 'because in our pursuit of whales, 
 which keep near the sides of it, but are not to be met with in it, we run 
 down along the sides, and frequently cross it to change our side ■ and, in 
 crossing it, have sometimes met and spoke with those packets, who were 
 in the midst of it, and stemming it. We have informed them that they 
 were stemming a current that was against them to the value of three miles 
 an hour, and advised them to cross it and get out of it ; but they were 
 too wise to be counselled by simple American fishermen. When the winds 
 are light,' he added, ' they are carried back by the current more than they 
 are forwarded by the wind ; and if the wind be good, the subtraction of 
 seventy miles a day from their course is of some importance.' I then 
 observed that it was a pity no notice was taken of this current upon the 
 charts, and requested him to mark it out for me, which he readily com- 
 plied with, adding directions for avoiding it in sailing from Europe to 
 North America. I procured it to be engraved, by order from the General 
 Post Office on the old chart of the Atlantic, at Mount & Page's, 
 
Tower Hill, and copies were sent to Falmouth for the captains of the 
 packets, who slighted it ; however, it has since been printed in France, 
 of which edition I hereto annex a copy. 
 
 " This stream is probably generated by the great accumulation of water 
 on the eastern coast of America between the tropics, by the trade-winds 
 which constantly blow there. It is known that a large stream of water, 
 ten miles broad, and generally only three feet deep, has by a strong wind, 
 had its water driven to one side and sustained, so as to become six 
 feet deep, v^'hile the windward side was laid dry. This may give some 
 idea of the quantity heaped upon the American coast, and the reason of 
 its running down in a strong current through the Islands into the Bay of 
 Mexico, and from thence issuing through the Gulf of Florida,and proceeding 
 along the Coast to the Banks of Newfoundland, where it turns off" towards, 
 and runs down through, the Western Islands. Having since crossed the 
 Stream several times in passing between America and Europe, I have been 
 attentive to sundry circumstances relating to it, by which to know when 
 one is in it; and, beside the Gulf weed with which it is interspersed, I find 
 that it is always warmer than the sea each side of it, and that it does not 
 sparkle in the night. I annex hereto the observations, made with the 
 thermometer in two voyages, and may possibly add a third. It will 
 appear from them that the thermometer may be a useful instrument to 
 the navigator, since currents coming from the northward into southern 
 seas will probably be found colder than the water of these seas, as the 
 currents from southern seas into northern are apt to be warmer." — 
 (^American PhUos. Trans., vol. II., Old Series.) 
 
 In April, 1854, the difference of temperature in 150 miles nearly off the 
 Balize, was ten degrees. The temperature of the outer water was 78° 
 nearly that of the Gulf Stream at this season of the year. 
 
 We are now prepared to collect and group on a chart chiefly thermal, 
 the facts relating to the Gulf Stream. I shall introduce what is known 
 in a general way of its current incidentally. 
 
 Passing by the Floi'ida Keys, the Stream v^-as found last summer to have 
 a tempf rature of 84°. This is 8° above the mean temperature of the 
 month of June at Key West, as given in the Surgeon General's Eeport. 
 
 The currrent here has little strength — enough, however, to make vessels 
 seek its aid in working to leeward from Key West, and enough there 
 to cause stearaei's to seek it in their course by standing out towards the 
 middle of the passage between the Florida Keys and Cuba. 
 
 Issuing through the Straits of Florida and passing between the eastern 
 coast of the Peninsula and the Bahamas, it is turned northward by the 
 land which confines and directs it The direction of the stream here is 
 nearly nortli by a little west of north. Its velocity varies from three to 
 five nautical miles per hour, and its summer temperature (July and August), 
 at fifteen fathoms below the surface, is about — °, varying with the season. 
 This is an interesting section. It shows, instead of an unfathomable 
 Gulf, worn by the rushing waters of this great stream, quite a moderately 
 deep passage, with two streams in it — one passing rapidly to the north, 
 and^the other slowly to the south, one unmistakably tropical, the other as 
 unmistakiil>ly Polar in its origin — the lower saving the bottom of the sea 
 from the great attrition assumed for it by theorists. 
 
 Follow now the course of the Stream as it bends into the bight between 
 
i; 
 
 Cape Florida aud Cape HaLteras. Recollect that each one of these 
 curves is the result of raaTiy data, all independent ; that the cold wall, 
 the axis, the second minimum, and second warm streams are four independent 
 sets of observations ; that the positions in each section, and in the several 
 sections, are results of independent observations ; that the results confirm 
 each other remarkably, not only in passing from the surface to the greatest 
 depths, but from position to position, and from section to section. The 
 stream off Cape Canaveral has a northwardly set, and between that Cape 
 and St. Augustine, begins to bend to the eastward of north. The stream 
 between St. Augustine and Hatteras takes the general direction of the 
 coast, making 5° of easting in b'^ of northing, curves to the northward, 
 and then runs eastward so as to make about B° of easting, in 3° of 
 northing. In the latitude of 38°, between Cape Charles and Cape 
 Henlopen. it turns quite eastwardly, having then a velocity of only between 
 one and two miles an hour. 
 
 That this general sweep follows the coast vin "ler water, (the coast line), 
 the curve of one hundred fathoms, and the hill ranges of Mafnt, Craven 
 and Sands, seem in a general way fully to establish. That it may be 
 modified by other circumstances is not denied, but merely that is not de- 
 termined by them. 
 
 The after progress of this mighty stream and of its branches remain yet 
 to be traced as this part has been, and the variations from the general 
 conditions presented by oha;iges of seasons, winds and storms. 
 
 These, we may hope, unless the success which has hitherto attended 
 these labors be for the future denied them, accurately to determine, and 
 perhaps at some future day to present to your attention." 
 
 "The existence of a northeast current on the coast of Japan was noticed 
 by Cook, Kinzenstern and other explorers, and has, of course, not escaped 
 the attention of more recent intelligent navigators, but I believe no syste- 
 matic series of observations upon it have hitherto been made. 
 
 The Japanese ai-e well aware of its existence, and have given it the 
 name of "Kuro-Siwo," or Black Stream, which is undoubtedly derived 
 from the deep blue color of its water, when compared with that of the 
 adjacent ocean. 
 
 The fountain from which this stream springs is the great equatorial 
 current of the Pacific, which in magnitude is in proportion to the vast 
 extent of that ocean, when compared with the Atlantic. 
 
 Extending from the Tropic of Cancer, on the north, to Capi'icorn — in 
 all probability — on the south, it has a width of near three thousand 
 miles ; and with a velocity of from twenty to sixty miles per day, it sweeps 
 to the westward in uninterrupted grandeur around three-eighths of the 
 circumference of the globe, until diverted by the continent of Asia, and 
 split into innumerable streams of the Polynesian Islands, it spreads the 
 genial influence of its warmth over regions of the earth, some of wliich — 
 now teeming in prolific abundance — would otherwise be but barren wastes. 
 
 One of the most remarkable of these off-shoots is the Kuro-Siwo, or 
 Japan Stream, which, separated from the parent current by the Bashee 
 Islands and south end of Formosa, in lat. 22° north long., 122° east, 
 is deflected to the northward along the east coast of Formosa, where its 
 
strength and character are as decidedly marked as those of the Gulf 
 Stream on the coast of Florida. This northwardly course continues to 
 the parallel of 26° north, when it bears off to the northward and east- 
 ward, washing the whole southeast coast of Japan as far as the Straits of 
 Sangar, and increasing in strength as it advances, until reaching the chain 
 of islands to the southward of the Gulf of Yedo, where its maximum 
 velocity, as shown by our observations, is 80 miles per day. 
 
 Its average strength from the south end of Formosa to the Straits of 
 Sangar is found to be from 35 to 40 miles per twenty-four hours at all 
 seasons that we traversed it. 
 
 Near its origin the Kuro-Siwo, like the Gulf Stream, is contracted, and 
 is usually confined between Formosa and the Majico-Sima Islands, with a 
 width of one hundred miles. But to the northward of this group it 
 rapidly expands on its southern limit, and reaches the Lew-Chew and 
 Bonin Islands, giving it a width to the northward of the latter of about 
 five hundred miles. 
 
 To the eastward of the meridian of 143° east, in latitude 40° north, the 
 stream takes a more easterly direction, allowing a cold current to inter- 
 vene betweeen it and the southern coast of Yesse, where the thermal 
 change in the water is from 16° to 20°; but from the harrassing prevalance 
 of fogs during our limited stay in that vicinity, it was impossible to make 
 such observations or experiments as to proveconclusively the predominant 
 direction of this cold current through the Straits of Sangar, particularly 
 as the tide ebbs and flows through them with great rapidity. Yet, from 
 what we have, I am inclined to believe that it is a current from the Arctic 
 Ocean running counter to the Kuro Siwo, and which passes to the west- 
 ward through the Straits of Sangar, down through the Japan Sea, between 
 Corea and the Japanese Islands, and feeds the hyperborean current on the 
 east coast of China, which flows to the southward through the Formosa 
 Channel into the China Sea. For to the westward of a line connecting 
 the north end of Formosa and the southwestern extremity of Japan there 
 is no flow of tropical waters to the northward, but on the contrary, a cold 
 counter current filling the space between the Kuro-Siwo and the coast of 
 China, as is distinctly shown by our observations. As far as this cold 
 water extends off the coast, the soundings are regular and increase 
 gradually in depth, but simultaneously with the increase of temperature 
 in the water the plummet falls into a trough similar to the bed of the 
 Gulf Stream, as ascertained by the United States Coast Survey. 
 
 In addition to the resemblance in general character between the Gulf 
 Stream and Kuro-Siwo, there are other analogies which I shall presently 
 mention. Bat in the first place I will call your attention to the chart upon 
 which they are traced, to show the striking coincidence in the recurvation, 
 not only of these oceanic streams, but also to the general coinci- 
 dence in their recurvation with that of the storms of the Northern 
 Hemisphere. Mr. Redfield is of the opinion that the recurration of storms 
 between the parallels of 20° and 30° north and south latitude in all parts 
 of the world, as shown by observation, is but partially dependent upon 
 the influence of land, and is "to be ascribed mainly to the mechanical 
 gravitation of the atmospheric strata as connected with the rotative and 
 orbital movements of the different parts of the earth's surface." (Naval 
 Mag., 18SG, p. B18. ) 
 
In the American Coast Pilot, edition of 1887, pp. 666, 667, Mr. Red- 
 field fiirtiiermore says : — "■ The Gulf Siream from Florida to Newfoundland, 
 is for the most part imbedded or stratilied upon a current which is setting 
 in the opposite dii-ection in its progress from tlie Polar regions. By its 
 action, the great stream of drift ice from the Polar Basin is brought within 
 the dissolving influence of the Gnlf Stream ; and the Grand Bank itself, 
 perhaps, owes its origin to the deposites which have resulted from this pro- 
 cess during a long course of ages. The icebergs being carried southv/ard 
 by the deeper Polar current, their rapid destruction is here effected by the 
 tepid water of the Gulf Stream. These two streams of current, like 
 other currents, both atmospheric and aqueous, pursue each its determinate 
 course — the Gulf Stream being thrown eastward by the greater rotative 
 velocity, which it acquired in latitudes nearest the equator, and the Polar 
 current being thrown westward along the shores and soundings of the 
 American continent and its contiguous ocean depths, by the tardy rota- 
 tion which it derived in higher latitudes. Were the influence of winds 
 wholly unfelt upon the ocean, it is probable that the same system would 
 still be maintained in all its essential features by the mechanical infliuence 
 of the earth's rotation, combined with an unstalale state of equilibrium." 
 
 And Lieut. M. F. Maury, in a paper on the Gulf Stream and currents 
 of the sea, read before the National Institute, April 2, 1844, says: "A 
 geodetic examination as to the course of the Gulf Stream does not render 
 it by any. meaus certain that it is turned aside by the Grand Banks of 
 Newfoundland at all, but that in its route from the coast of Georgia as far 
 towards the shores of Europe as its path has been distinctly ascertained, 
 it describes the arc of a great circle as nearly as may be. Following the 
 line of direction given to it after clearing the Straits of Florida, its course 
 would be nearly on a great circle passing through the poles of the earth. 
 That it should be turned from this, and forced along one inclining more 
 to the east, requires after it leaves these Straits, the pressure of a new 
 force to give it this eastward tendency ; and have we not precisely such 
 a force in the rate at which diff'erent parallels perform their daily rounds 
 about their axis ? In consequence of this the stream when it first enters 
 the Atlantic from the Gulf, is carried with the earth around its axis at 
 the rate of two miles and a half a minute faster towards the east than it 
 is when it sweeps by the Grand Banks of Newfoundland. 
 
 " That this explanation, as to its eastward tendency should hold $rood 
 a current setting from the north towards the south, should have a west- 
 ward tendency, accordingly, and in obedience to the propelling power de- 
 rived from the rate at which different parallels are whirled around in 
 diurnal motion, we find the current from the north which meets the Gulf 
 Stream on the Grand Banks, taking a southwesterly direction as already 
 described. It runs down to the Tropics by the side of the Gulf Stream, 
 and stretches as far to the west as our shores will allow." 
 
 That this theory of rotative influence, may, or may not be correct, it is 
 not my province to discuss, but I was forcibly struck with these coinci- 
 dences of recurvation, when the tracks of the Gulf Stream and Kur'o-Siwo, 
 together with the paths of hurricanes, were traced upon the same chart ; 
 and I have made these quotations to show what hypotheses are entertained 
 by some of the eminent men who have given much attention and study to 
 the subject ; and from a conviction that they are in some measure at 
 
9 
 
 least, sustained by the results of our observations upon the Kuro-Siwo, 
 foi', notwithstanding the configuration of the eastern shores of the conti- 
 nents of America and Asia are undoubtedly the original caui.e of the de- 
 flection to the northward, of the whole of the equatorial current of the 
 Atlantic, by the Gulf Stream, and of a portion of that of the Pacific by 
 the Kuro-Siwo or Japan stream ; yet, were no influences such as Mr. Red- 
 field and Lieut. Maury refer to operating upon these streams, would not 
 their natural inclination from the inertia of their westward flow be to hug 
 the coasts, and wash their whole length to the Arctic Sea, or until that 
 inertia was overcome by their friction against the continents? Yet this 
 is not the case in either instance, for it has been well established by Mr. 
 Bache, in his last address, that a counter current,' flowing to the southward 
 and westward, intervenes between the Gulf Stream and the coast of the 
 United States, as far as the Peninsula of Florida ; and, as I have before 
 stated, as far as our observations extend, they prove conclusively that there 
 is a very important counter current intervening between the Kuro-Siwo 
 and the main coast of Asia. 
 
 I am not precisely aware of what the thermal change is, in passing into 
 or from these cold strata in the Gulf Stream, but those in the Kuro-Siwo 
 were indicated by a depression of only a few degrees ^in the water ther- 
 mometer, and therefore should more properly be termed cool strata as 
 compared with the rest of the stream, for in all instances these strata 
 maintain a superior temperature to the atmosphere above them ; and if 
 the hyperborean current is, as I have supposed, entirely separated from 
 the Kuro-Siwo by its passage through the Straits of Sangar, to the west- 
 ward of the Japan Islands, I am inclined to think that there is no counter 
 current underlying the Kuro-Siwo, as is the case with the Gulf Stream. 
 This, however, can only be determined by experiments with the deep sea 
 thermometer, and the usual apparatus for determining submarine currents, 
 none of which were made by the expedition, as its special object was of 
 primary importance, and all other subjects within the field of our observa- 
 tions were necessarily of subordinate consideration, and were obliged to 
 be made as oppoi'tunity and the ordinary facilities of our situation would 
 permit. Lieut. M, F, Maury says, that " the maximum temperature of 
 the Gulf Stream is 86°, or about 10° above the ocean temperature due to 
 the latitude." This maximum temperature coincides with that of Kuro- 
 Siwo, as shown by the daily means of our observations, but the difference 
 between the temperature of the Kuro-Siwo and the "ocean temperature 
 due to the latitude," is, by the ^aol^ observations, shown to be greater, 
 amounting on an average to abou^;ip°. 
 
 The influence of Kuro-Siwo u^|fi^Ue climate of Japan .and the west 
 coast of North America, is as jmjg^Bf^'expected, as striking, as that of 
 the Gulf Stream on the coasts^oorclering the North Atlantic. From the 
 insular position of Japan, wifh the intervening sea between it and the 
 continent of Asia, it has a. moi;^e^,equabl^. climate -than we enjoy in the 
 United States; and since the: countei^current of the Kuro-Siwo does not 
 make its appearance on the eaefSrn shores of the islands, south of the 
 Straits of Sangar, and as these' islands, in their geographical position, 
 have a more eastwardly direction than our coast, the Kuro-Siwo, unlike 
 the Gulf Stream, sweeps close along this shore, giving a milder climate 
 of that portion of the empire 'than is enjoyed in corresponding latitudes in 
 the United States. 
 
10 
 
 The softening influence of the Kuro-Siwo is felt on the coasts of Oregon 
 and California, but in a less degree, perhaps, than that of the Gulf Stream 
 on the coasts of Europe, owing to the greater width of the Pacific Ocean 
 over the Atlantic. 
 
 ' Still, the winters are so mild in Puget's Sound, in latitude 48° north, 
 that snow rarely falls there, and the inhabitants are never enabled to fill 
 their ice houses for the summer ; and vessels trading to Petropaulowski 
 and the coast of Kamtskatka, when becoming unwieldy from accumulation 
 of ice on their hulls and rigging, run over to a higher latitude on the 
 American coast and thaw out, in the same manner that vessels frozen up 
 on our own coast, retreat again into the Gulf Stream until favored by an 
 easterly wind. 
 
 I 
 
 The first delineation of the Gulf Stream was made by Dr. 
 Franklin, as Prof. Bache believes, in 1770; the cause of the 
 current being attributed by him to the trade-winds. The 
 trade winds are currents of air ; and it is now generally 
 acknowledged that heat is the chief cause of atmospheric 
 currents. From this fact, we have been led to inquire 
 whether — while admitting theii? important influence in acce- 
 lerating the flow of the water currents. — the trade-winds might 
 not be merely secondary to Solar heat as the primary moving 
 cause of both. 
 
 The great Equatorial current, " extending from the tropic 
 of Cancer on the north, to Capricorn in all probability on the 
 south, has a width of near three thousand miles ; and with a 
 velocity of from twenty to sixty miles per day, it sweeps to 
 the westward in uninterrupted grandeur around three.-eights 
 of the circumference of the globe." 
 
 Now, this current — over which the sun travels in his an- 
 nual course — is a heated current ; and caused, we believe, in 
 the following manner. 
 
 The water of the ocean, at the ' equator and within the 
 tropics, is heated not only at its surface, by the surrounding 
 atmosphere, but is also heated at its bottom. This heat is 
 derived from the earth, its teipperature being elevated by the 
 sun's rays passing through the wa-ter. The water thus heated 
 by its contact with the earth, rises from its depths below to 
 the surface, where it attains the temperature of 87° Fahr. 
 
11 
 
 The vacuum formed by the rising water is supplied at the 
 bottom by the water flowing to it from the colder regions. 
 
 This equatorial surface current takes a westerly direction 
 in consequence of 'the earth's diurnal motion, and proceeds 
 along the north coast of South America to the Gulf of Mexico, 
 where meeting with the North American Continent, it receives 
 a direction northeast along the coast line to the Grand Banks 
 of Newfoundland, and afterwards more easterly, as presently 
 will be described. 
 
 This immense body of surface water, which Prof. Bache 
 found to differ in temperature widely on the upper and under 
 portions, and consequently in density, loses gradually its heat 
 as its progresses northward, until it meets with water colder 
 than itself, which reduces it to 40°, (at which point water is 
 heavier than at any temperature above or below it), in this 
 manner meeting with water colder, and consequently lighter 
 than itself, it becomes an under current to the great Polar 
 current flowing in an opposite direction above it. Previous 
 to their meeting on the Grand Banks, the course of the equa- 
 torial or parent stream would be, from the direction given to 
 it by the coast line, nearly east-northeast. The course of the 
 Polar current would be, from the direction given to it by the 
 east coast of Greenland, nearly southwest, as is evident on 
 reference to the charts of the Ocean currents. 
 
 At the point of meeting of the two opposing currents, an 
 important change takes place in the direction of their line of 
 motion, resulting from the operation of two laws ; the law of 
 opposing forces, and the law which governs water at the 
 temperature of 40°. 
 
 The Equatorial current having a different density and 
 velocity in its upper and lower portions, would, under these 
 conditions, be separated into two branches on meeting with 
 the Polar current ; at the point of bifurcation, the upper 
 portion being' at a temperature above 4€°, and consequently 
 lighter, would become deflected still more to the eastward^ 
 Sind constitute in this branch the Gulf Stream proper ; while 
 
12 
 
 the lower portion and main branch being at 40°, the point of 
 greatest density, and consequently heavier, would become an 
 under current to the one above it, proceeding onward to its 
 destination at the Pole: 
 
 Turning now to the Polar current, flowing southward, we 
 have only to apply the same laws to understand its course ; 
 the upper portion on becoming elevated above the tempera- 
 ture of 40°, and consequently lighter, would, on m.eeting with 
 the upper portion of the parent current, become deflected 
 still more to the westward, and constitute in this branch the 
 inshore, or counter current ; while the lower portion, and 
 main branch, being at the point of greatest density, and con- 
 sequently heavier, w^onld become an under current to the 
 parent stream above it, and proceed onward to its destination 
 at the Tropics. 
 
 And we might add, as an assisting cause for the counter cur- 
 rent flowing between the Gulf Stream and theS coast, the in- 
 fluence of the great rivers, which pour out their waters as 
 surface currents against the stream. 
 
 In the rotary theory quoted in the lectureabove, it is said 
 alluding to the Gulf Stream : " Following the line of direc- 
 tion given to it, after clearing the Straits of Florida, its 
 course would be nearly a great circle passing thi ough the 
 poles of the earth. That it should be turned from this, 
 and forced along one inclining more to the east, requires after 
 it leaves these Straits, the pressure of a new force, to give it 
 this eastward tendency." Now, that it should be turned from 
 the course of a great circle passing through the poles of the 
 earth and forced along another, inclining more to the east, 
 would seem to imply that it did not pass to the pole at all; 
 but as this cannot be its meaning, consistently with the exist- 
 ence of a Polar current, it is added, " That this explanation 
 as to its eastward tendency should hold good, a current 
 setting from the north towards the south should have a west- 
 ward tendency," we infer, therefore, the meaning to^be, that 
 a part only passes to the east, and another part to the pole ; 
 
if this be so, we can have no objection, as it would be so far 
 our own theory ; if, however, the language does not warrant 
 the construction that the stream is divided into two branches, 
 one going to the east, and the other to the north, then there 
 would seem to be a discrepancy somewhere. Lieut. Bent 
 says : — That this theory of rotative influence, may, or may 
 not be correct, it is not his province to discuss, and adds, that 
 it is in some measure, at least, sustained by their observa- 
 tions upon the Japan Stream. And Capt. AVilkes, in a 
 valuable work recently published upon the winds, &c., has 
 shoAvn it to be not at all applicable to atmospheric currents, 
 however it may be to vapour and water currents. 
 
 Such would seem to be the natural results of the law^s 
 we have mentioned which govern the two opposing streams ; 
 and thus would be completed the circulation of these magni- 
 ficent currents — a system of imposing grandeur. 
 
 The following diagram is a section of the earth's surface, 
 including the North Pole and the Equator, and is intended to 
 represent the flow of the Polar and Equatorial currents. 
 
 &^ 
 
 a. Equator, place of be^nning. 6. Water rises to surface, c. Equatorial north surface current- d. 
 Meeting of the waters, e. Continuation of the equatorial north surface current, now become the north 
 polar under current. /. Pole. g. Polar south surface current, h. Continuation.of the polar south 
 •urfaee current, now hecome the equatorial under current to the place of heginning a. j. Bottom of sex 
 
1-1 • 
 
 Lieut. Bent, in his lecture, speaks of the Japan Stream as 
 being identical almost with the Gulf Stream : its equatorial and 
 counter currents are the same ; one material difference, how- 
 ever, exists, there is no polar surface current flowing southward 
 through Behring's Straits ; on the contrary, there is a slight 
 surface current flowing north, and there is in all probability 
 no under current at all flowing southward from the Pole ; for 
 such would reverse the law of temperature, as we find it in 
 the North Atlantic ; how then is this anomaly to be accounted 
 for '? Capt. Cook remarks of Behring's Straits : " It is formed 
 in its narrowest part by two remarkable head-lands, the dis- 
 tance between these two points is about thirty-six miles. The 
 water has an equal but not great depth ; on both sides of the 
 Straits the soundings are the same at the same distance from 
 the shore, that near the land he never found more than 23 
 fathoms, and no where more than 30 fathoms ; there are a 
 few small islands scattered here and there along the Strait, 
 and one of some size — St. Lawrence, or Clerk's Island — lies 
 at a short distance south from its entrance ; by the end of 
 August, the thermometer sinks to the freezing point, and 
 north of the two Capes, there is always a store of ice, 
 which the heat of summer is quite powerless to disperse. It 
 need scarcely be added, that the Strait is frozen over every 
 winter." {McCulJocKs Geo. Die.)— (Cook's Third Voy. II., 
 page 457.) 
 
 We think this establishes the fact, that there is no adequate 
 passage through the Straits ; it is both too narrow and too 
 much obstructed ; it is therefore natural to infer that the Sea 
 or Gulf of Kamstcatka is the terminus of circulation for the 
 Great Pacific Stream ; and as the climate and waters south 
 of the Straits, comprised within this basin, are comparatively 
 mild, in consequence of the warmth imparted by the Equato- 
 rial Stream, may we not reasonably infer a like resemblance 
 at the Polar basin of the North Atlantic, and find therein a 
 confirmation, if need be, of the recent great discovery by Dr^ 
 Kane, of an Open Polar Sea. 
 
15 
 
 The design of this great system of circulation is apparent in 
 the ameliorating influences which the warm currents dispense 
 over regions in the higher temperate and frigid zones, which 
 otherwise would be but barren and inhospitable wastes. 
 
 And within the Tr6pics, where if calms were of any fre- 
 quency, the heat would be destructive to all life, the great 
 design is also apparent in the refreshing influences which the 
 constant circulation of the winds and waters dispense, exhibit- 
 ing in all alike, the wonderful wisdom and power by which 
 the whole is governed. 
 
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