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eye of Captain Budd, or that of Mr. Moeller, as either of them may be able to supply the longitude of the place where it was thrown over, which from the latitude given, would appear to give it more than ordinary interest. The preceding one No. 106c affords another very interesting proof of the eddy current, setting to the southward from the Eastern edge of the Gulf Stream.

THE BOTTLE CHART.

SIR.-I was surprised, if not sorry to find that, Sir John Ross, himself distinguished in scientific research, should consider it to be his duty to write condemnatory of the system of research proposed in your Bottle Chart. I say research, for it conveyed to my mind but the idea of challenging investigation into a large and extensively useful field of ascertainable facts, though Sir John assumes that it asserts the currents to have run from the point at which each bottle was thrown overboard to where they were each picked up, and then proceeds "to expose" as he says, the "bottle fallacy." The fallacy, however, consists in his having attempted, and attributed to any one that attempts, to deduce a system from insufficient data; finding this impracticable he pronounces the facts contained in your chart to be fallacies, and then endeavours to do away with them; but facts have ever been stubborn things, and will not be thus easily put aside.

This misuse of data was anticipated, and I had thought sufficiently guarded against. So thought also the writer of that excellent letter which follows that of Sir John, who "" says, as properly observed," the lines on the chart are merely intended to connect the places of departure and termination of the bottles, and not to shew (as may be imagined, by those who are not seamen,) in every case the true direction which the currents and drifts pursued. I had thought your proposed system unquestionable, as the true inductive system, and still remain convinced that it is to collect all ascertainable facts, from them collated to deduce their law of action, and from thence ascertain their governing law, thus "tracing nature up to nature's God." Sir John perhaps having run the range of the sciences has but found all to be vanity; true indeed! such is the case as comparable to the eternally true, yet are all truths of value in their just order and degree. Such then being the case, I hope you will continue your highly interesting, and what will prove to navigation, eminently useful investigation; and though many may be found to cavil at it, none who have experienced the advantage of following certain routes because of the favourable winds and currents which had obtained on them, but will duly appreciate the advantages that will be obtained to navigation by your map being continued and enlarged by the data which will flow in. These data will present difficulties to the captious, as a collection of isolated unmanageable facts, partial in their action and inadequate to the discovery of anything useful but to the philosophic spirit that will examine and generalize the discrepancies, banish dis-similar things then seen to follow a similar law, evidence of a mechanism, the character of which is universality, and

the result of which is " very good," and in turn becomes the proof of the design of a law with which they had appeared to be at variance.

The several instances cited by Sir John, as contradictory of the facts, contained in your map, and as falsifying the proposed scheme of inquiry may be satisfactorily accounted for. Reconciled difficulties or dis-similar facts shewn to conform to a similar law are additional proofs of the truth of that law to which they conform.

The first instance cited by him, being in a tide, off Dover influenced by local causes, and prevented from following the law in its general aspect, is not a case pertinent to the argument. Yet, there does not appear much difficulty even in this, as it is obvious that he himself was in doubt whether the desired ebb had made or not. Our desires materially modify the results which we receive, and the bottle was thrown over to ascertain the fact. Therefore, though the log shewed two knots of ebb, this was not the case at the surface, else why the doubt expressed in the experiment? And, as Sir John says, the bottle may have taken the direction of the Downs, impelled by the wind, as we know that a strong wind will arrest even a surface tide. That it did not do so in this case the log is no proof, as the log-ship sinks below the surface water when not held up by the action produced by a somewhat tightened line which will hardly have been the case in the instance alluded to.

The value of the second experiment, the loaded wood and bottle, may be admitted, and the truth of the theory proposed remain entire. The difference consists in the extent of action. The wood was accelerated less than the bottle by the wind, but when the wind was adverse to the current, was less retarded. Then if Sir John's wood experimenter were equally good with the bottle, and set off at the same time and point of departure, they would reach nearly the same destination.

The results of the bottle experiments prove that though there be currents and counter currents in the water and atmosphere, the prevailing currents were such on the route of each bottle, as to bring them to where picked up. Hence though they may have "worked a traverse" the course and distance made good was from point of departure to point of termination, and had a vessel passed over the route of any one of these bottles she would have similarly, though not to the same amount been influenced with that bottle.

The statement relative to the Defence's top-mast but argues that it had got into one of those whirling eddies that are a consequent result of the law of currents, the economy of which must also deserve investigation.

The experiment of the loaded bottle with an empty bottle, is similar in principle to that of the second experiment, and open to the same answer; while it further illustrates what all admit, that a loaded bottle being more immersed offers more resistance to motion in the water, and offers less surface for the wind to act on than an empty bottle.

The fact relative to the icebergs is valuable testimony to the truth of the proposed scheme of acertaining the direction of currents, as it quite accords with what appears to be a likely effect of the governing forces of the southerly motions, from a consideration of which it must appear that the southerly currents spoken must be, in the absence of other courses, greatest at the surface. Therefore, though the icebergs

were carried southward, and though five-sixths immersed they must have been so carried by a comparatively, if not actually, surface cur

rent.

I doubt not, but that a strict examination will prove that a surface current passes icebergs in the same direction in which they move, the icebergs being retarded by being so immersed, and the lower water not having equal rapidity of motion with the upper; if so it may account for the infrequency of collisions with them, and what beauty, what design, what fitness to the weakness and wants of man!

Sir John's account of the icebergs going south may account for the Alexander's bottles reaching Staffa and Donegal, by a current which is, perhaps, referable to the earth's motion.

Then of the many reasons why Sir John's copper cylinders should arrive at any destination, save that which a little reflection would assign them, viz. the bottom, I shall select but one, as sufficient to account for their not arriving in terra cognita. The galvanic action (especially between wind and water,) between the metals, would be to destroy their junction, and thereby render the cylinders pervious to water, and this long before the period necessary for their transit could expire.

The contrariety between the winds and currents instanced by Sir John, obtains but partially, for it is undeniable that the currents are constantly being caused, controlled, or modified by the action of wind, suffice it to mention two instances, though hundreds will suggest themselves to those who observe such things. The current on the Lagulhas Bank is altered and controlled by the wind till the gravitating force of the water overcomes the force of the wind, and the stream bursts back with double rapidity into its former direction even against a gale.

And on the Gold Coast the usual easterly current is arrested by the the south-east winds, which blow home to the coast in June and July, and gives place to a current running to the W.N.W. from Cape Palmas, and continues during the months of June and July, sometimes for a longer period depending on the winds. But while we admit the fact that the winds influence the currents, and even considerably, we must not fancy that they are the sole causes of currents. The similarity of direction of each in general, may give rise to this idea; but it is evident that they are both due in the main to the same causes, which act similarly, though not alike extensively, viz. the earth's motions. The difference consists in that while the air is more mobile than water, its inertia is comparatively nothing, and while air may be extensively altered aad influenced by heat, or its absence, water remains apparently unaffected; one ceases to act, at least sensibly so, while this the other goes forward.

I would then propose that you should continue to encourage the prosecution of the enquiry, but would beg to suggest the advantage to be derived from white bottles being used (coloured white in the blowing with an oxide of arsenic,) because of their being more easily seen, in order that they may be picked up on the route, their place, latitude, and longitude registered; and again started with the added information. I remain, &c. To the Editor, &c. G. FISHBOURNE, Commander R.N. ENLARGED SERIES.-NO. 6.-VOL. FOR 1843. 3 G

VARIATION OF THE COMPASS.

(Continued from p. 211.)

Royal Observatory Greenwich, May 15th, 1843,
Magnetical and Meteorological Department.

MEAN MAGNETIC DECLINATION FOR 1843.

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Ar the Arru Islands, Christianity was introduced many years past by the Dutch at Amboyna, and nearly all the principal people there profess the Christian religion. The Ki Islands, however, appear to have been neglected by the Dutch missionaries, and the consequence is, that many of the natives have been converted by the Mahomedans of Ceram, who have several priests on the island.

The commerce of the Ki Islands is inconsiderable when compared with that of the Arrus, attracting only about a dozen prahus annually from Celebes, Butou, and Banda.

These obtain tortoise-shell and cocoa-nut oil. The last is the staple produce of the group, and is of superior quality, in exchange for the foreign articles in general use amongst the natives on the islands.

Refreshments in the form of yams, pigs, poultry, cocoa-nuts, Indian-corn and fruit, are to be obtained here in greater quantities, and at a cheaper rate than on any island in these seas that I have visited. Prahus and boats of all sizes, built of the excellent timber with which the island abounds, form one of the principal articles of export; and the construction is the chief occupation of the inhabitants when they are not employed in the cultivation of their plantations. Vessels going to the Arru Islands touch here to obtain boats for trading among the smaller islands, and a large portion of the prahus navigating these seas are built here. The small boats especially are highly prized for their durability and swiftness, and it is singular that these people have hit upon a model closely resembling that adopted for fast-sailing vessels in England.

The Ki group is well situated for communication with Port Essington, as the monsoons blow fair for making the passage either way. The harbour of Kidulan, on the north-west side of the Lesser Ki, in which we anchored, was surveyed by Captain Stanley; it is an excellent anchorage being sheltered to seaward by several islands of considerable extent, between which there are navigable channels.

The Britomart left the Ki Islands on the 29th of June, and arrived at Banda

* Just published, see notice of Charts.

on the following morning. The port of Banda is closed against foreign merchant vessels, and is rarely visited by those under the Dutch flag, with the exception of two or three ships which arrive annually from Java, bringing rice and European luxuries for the supply of the inhabitants, and taking away the produce of the nutting plantations. The population consists of about 20 Europeans in the civil and military employ of the government, 250 soldiers, all of whom are natives of Celebes and Amboyna, with the exception of about 30 Europeans, 50 Chinese, 3,000 or 4,000 convicts, about the same number of slaves, perhaps, 1,500 free people or burghers, many of whom are of Dutch extraction, and 200 or 300 natives of Timor-laut and Baba. The aboriginal inhabitants of Banda have totally disappeared, in fact, have been exterminated. The only European merchant in Banda is an agent of the Dutch Commercial Society, who had lately arrived; but the Chinese are all engaged in commerce, are more wealthy than the others, possess two small vessels and several prahus, which are employed in trading with the natives of Timor-laut and New Guinea; but owing to the amount of duties at Banda, the Chinese find it difficult to compete at the places they visit with the traders from Singapore. During this year, the voyage of one of the vessels belonging to the Chinese above mentioned, had been rendered unprosperous by the arrival, in the same port of New Guinea, of the Lullworth, an English merchant vessel, that has several times visited Port Essington; the goods brought by the latter being better suited to the tastes of the natives, and, therefore, enabling her to buy up all the nutmegs, the most valuable produce of that part of New Guinea. A few prahus from Ceram, New Guinea, and Ki Islands annually visit Banda; but the trade on the whole is inconsiderable.

Banda owes its chief and almost sole importance to the nutmegs produced there. The parks (as they are called), in which the nutmeg trees are cultivated, are in the cultivation of several planters, of Dutch extraction, who are supplied with convicts by the government with the entire produce of the plantation at a very low price (about three halfpence per pound), and are strictly watched, that they may not dispose of any nutmegs to the traders. The annual produce is said to average between 300,000 and 400,000 pounds of nutmegs, and about one-fourth of that quantity of mace. Nutmegs are the only exportable produce of Banda, there being a great want of energy amongst the inhabitants, the cause of which, however, is sufficiently evident. The climate of Banda proves very unhealthy both to Europeans and natives, especially during the western monsoons, when the smoke from the neighbouring volcanoes rolls down upon the town, and renders it scarcely habitable. The two last residents lived only three months after their arrival at Banda. The secretary was acting resident at the period of our visit.

The Britomart left Banda on the 6th of July, and at noon on the following day entered the Bay of Amboyna; but the wind being light and unfavourable, she did not anchor off the town before the morning of the 8th. We found here a large Dutch frigate, and a brig-of-war, which were attached to the Malacca station.

Amboyna is the capital of the Malaccas; the governor resides here, but makes occasional visits to the residencies under his control, which are as follows: -Banda, Ternata, Mandano, on the north-east end of Celebes, Coepang, on the south end of Timor, Cajata Bay, on Buru; and Wadhi, on the north coast of Ceram.

The last is a settlement that was formed in 1838, after the abandonment of Fort Du Bus, on the south-west coast of New Guinea. The island of Amboyna, with Sapagua and Harouka, contains about 35,000 inhabitants, the greater portion of whom are employed upon the clove plantations. Victoria is the capital; contains 4,000 inhabitants, about one-fourth of whom are of European extraction. There are also many Chinese inhabitants, who are chiefly occupied as traders, shopkeepers, and farmers of the revenue. Amboyna owes its importance entirely to the clove plantations, which are cultivated on the forced labour

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