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Notes On St. LAWRENCE NAVIGATION.
I ADMIRE very much the accounts given by Capt. Bayfield of the winds, action of the barometer, currents, &c., in those parts. The latter, however, in one point he has left undetermined, that is whether the current ever runs to the westward. Of this I have had indisputable proofs. Having taken the first of an easterly wind just outside of St. Pauls island, I have found a strong westerly current between that island and the Magdalens, and taking a fresh departure from the east end of the largest of those islands, and proceeding up with steady winds and smooth water, though hazy and thick, I narrowly escaped shipwreck near the end of Point de Monts, having been carried to the westward fifty-five miles in thirty-two hours. This, however, was an extraordinary case, as I found that a friend of mine, a man of great experience in those parts, bad felt a strong westerly current between Point de Monts and Green Island, at the same time, and which he deemed an unusual occurrence; as this current rarely extends above Point de Monts, the waters had probably been exhausted by long westerly winds; but from the experience of this and other passages under similar circumstances of winds, &c., I should recommend being upon your guard against a westerly current, say of one mile per hour, between St. Pauls island and Point de Monts; and to bear in mind that it has been experienced under certain circumstances much stronger and extending even to Green Island.
I would direct particular attention to Capt. Bayfield's accurate description of the sudden changes of winds; the easterly wind flying round after a short continuance to the north-westward, and as it abates veering to the south-westward. I have twice in September (homeward bound), and about fifty miles beyond the south-west point light and Cape Gaspé met with those winds; and the second time made the ship snug at once for the easterly wind, and kept her prepared (during the short interval of light airs and calm,) for the heavier N.W. wind that was to follow, which can be turned to good account in gaining the best position for running for St. Pauls when the wind has veered to the south-westward. There is a remarkable regularity in the action of those winds.
Light upon Anticosti east point.-I could never find a good reason for placing this light in that position, nor find any one to tell me, indeed few ever see it. I have seen it once only. However, at the best it could only be available to ships bound up, and the currents tend to set you from that danger, besides those parts of Anticosti are shunned by "saint or sinner.” While you are obliged to approach the Bird rocks or Magdalens, I think it extremely desirable for the safety of this navigation, that a light should be placed upon the Magdalens or Great Bird rock.
Local attraction.-İ believe that this is not so general on board of merchant ships as naval officers generally imagine, and when it does occur I think it frequently traceable to masses of iron being carelessly placed too near the binnacle, or by neglecting to get the compasses frequently magnetized. However, it does occur on board of some. But I think that the quantity of iron is seldom so great that it cannot by proper care be obviated; it is a correction which varies with every course; therefore great errors are likely to arise in allowing for it, and the cause ought, if possible, to be removed.
In the Gulf and Strait of Belle Isle.--I have never found my compasses affected by magnetic attraction in the Gulf; but in June 1843, having met with strong southerly winds in the Gulf, and made the coast of Newfoundland far to leeward of St. Pauls, I bore away for the Strait of Belle Isle. I had thick weather part of the run down, and when it cleared away I found some icebergs in sight, and passed eight large ones before we reached the entrance, and they were placed like sentinels along each side of the Strait (aground), and much low broken ice in the eddy between Belle Isle and the Narrows, which could scarcely be distinguished from the break of the sea, even in clear weather. The island was surrounded with icebergs, and several passed afterwards to eastward of it.
In the Strait I had every reason to think that my compasses were attracted toward the Newfoundland coast to the extent of half a point. Have not all the accidents occurred upon that side? Although I shortened my passage ten days by going this way, the risk of ice, fogs, and magnetic attraction are formidable dangers, and I strongly recommend it being avoided, unless in case of necessity, especially during the time of the ice.
Newfoundland Banks, and approaches to the Gulf of St. Lawrence.--I trust that the valuable labours of Capt. Bayfield will be extended to the Banks, which are upon some charts very defectively laid down; and the action of the currents not well understood. Lieut. Hare mentions the “ Banqueraour Bank” not being represented sufficiently extensive, and I have been credibly informed that less water has also been found upon that bank than the charts generally represent, and I know from my own experience that the “Green bank” is only half laid down, (that is the northern half,) upon the charts of Blachford and Imray, and their books are fit companions for such disfigured paper, as the charts of those publishers are. My account of their British Channel chart given in the Shipping and Mercantile Gazette, March 2nd, 1848, is fully better than I could give of their St. Lawrence and Newfoundland charts. The soundings upon the Green Bank are important in approaching the Gulf to check the latitude, should observations not be obtained.
The losses upon the south coast of Newfoundland have given rise to discussions upon the currents of those parts, and they have been attributed to the indrafts of bays, &c., while those on Cape Breton island are attributed to the Polar current. I shall here speak only of ships pursuing a fair track to the Gulf, and generally beyond the influence of tidal operations in shore; and I believe that those losses may with greater propriety be traced to the oversight of an intervening current between the Polar current and the out-setting current of the Gulf. Although those currents are mutable, and much influenced by local circumstances, yet three distinct currents are frequently in operation at the same time, and successively encountered by ships pursuing this route; first, the Polar current along the grand bank, but not extending within the stream of Newfoundland; they may feel this to 51° or 559 W.; and second, a due west current along the south coast to the stream of the western coast of Newfoundland, (say in line with Cape St. George and Cape Ray); an third, the out-set of the Gulf deflected to the southward by its accessions from the north, along the western coast of Newfoundland; and also by the westerly current along the south coast.
I believe that the erroneous application of the Polar current (when they were to the westward of it) have led those vessels to estimate their position too far southward, and they have been unexpectedly brought in contact with the indrafts, &c., up the coast, and thus thrown on shore; whilst others have detected the non-existence of the Polar current, and imagined that they had no current, while the westerly current was carrying them ahead of their account, and bringing them unexpectedly in contact with the southerly out-set of the Gulf, and thus thrown them upon the coast of Cape Breton Island, when they thought themselves in a fairway to St. Pauls.
Polar current.--I have repeatedly found this current very regular, but not exceeding twelve miles per day, on outward spring passages, though no doubt it is at times much stronger at that time. In the month of August, during a continuance of very fine weather, I have found no Polar current, both by observation and fishermen at anchor.; but always found my latitude by account, and observation to agree between the streams of Newfoundland as before given, and frequently found myself carried to the westward within those limits.
Making St. Pauls Island.- What I have found the most dangerous to a stranger in those ports is, making St. Pauls Island with the first of an easterly wind, and thick weather. In this case the ship is likely to be ahead by the westerly current, while this current may cause a greater deflection to the southward of the outset current of the Gulf, so that it runs almost directly across the entrance at St. Pauls Island. Captain Bayfield's remarks would lead you to anticipate this, but those remarks do not extend to currents beyond St. Pauls, and seamen's suspicions are apt to be lulled by finding the account and observations to have agreed for several days. I have, under such circumstances, more than once found myself disagreeably near to Cape North, when I intended to have passed to the northward of St. Pauls, and in one instance I had advanced with light westerly winds to within fifty miles of St. Pauls, with no error in my latitude in the space mentioned, when the wind veered to the eastward with haze and fog. I kept well up to endeavour to get soundings on the parallel coast of Newfoundland eastward of Cape Ray, and got 80 fathoms; and kept away under the two topsails, intending to creep on by soundings to St. Pauls, but the weather clearing a little I was surprised to find myself passing between Cape North and St. Pauls, and at 1 P.M., by cross bearings I found my latitude by land 26' S. of that by account in twenty-five hours. I do not consider those currents as permanent, but as being mutable, and much influenced by local cir
cumstances, and some of those circumstances we cannot estimate the effects of. It is the erroneous extension of the Polar current, that I would have guarded against, and for strangers to be upon their guard (when they lose the influence of that current,) against the westerly current, and then the southerly outset of the Gulf.
I trust that I have said enough to shew that a new survey of those parts is very requisite, that the soundings may be relied upon, and they are too often the only available guide; celestial observations being prevented by fogs when they are most required. And that some data may be obtained for estimating the currents beyond the Gulf, as Capt. Bayfield has given for those within it.
Marine Barometer.-Knowing from experience that this valuable instrument can be made so that implicit confidence may be placed in it, I have been mortified at finding only one tube out of three (that I had in the same case) on which I could depend. And, again, another which would not fall until the gale was actually upon us, and was consequently useless, except that it would then pretty nearly when we had the weight of the gale. Thus having only one tube out of four which was good, I am anxious to know whether this arose from some negligence on the part of the opticians, or whether there be some nice point in the principle of their construction which is not well understood.
March 30th, A.M., civil time, overcast atmosphere with drizzling rain, in second reefs of topsails, jib, and mizen; but although the barometers did not indicate worse weather than I had prepared for, yet between 9 A.M., and noon it came on so heavy with hard squalls and rain, that we were reduced to the two close-reefed topsails, and it did not abate any thing before 9 P.M., when the wind bad veered to N.W.b.N., and the atmosphere more clear, the barometers only fell to 29.20, while the same instruments under similar circumstances of atmosphere, direction, and force of the wind, had previously fallen as low as 28.50.
During the night of the 22nd, civil time, we were again reduced to the close-reefed topsails and reefed foresail; wind W.S.W.; cloudy with rain, and the baroineters at 29-90. During this gale we had a heavy sea, about four points to the northward of the wind, or W.N.W. This wild weather was succeeded by light airs and calms, with foggy weather, position 50 to 100 miles northward of Cape Finisterre: again on the night of the 26th, civil time, it blew a heavy gale with violent squalls between the N. and N.N.W., which was not indicated by the barometers. They have been carefully attended to and found to rise and fall together; the only difference being that mine always stood half a tenth above the ship’s. The Nautical Almanac shews full moon 19d. 9h. 19m., and the sun crossed the equator at about 23h. 10m. on the 19th, astronomical time.
Are those irregularities attributable to lunar and solar influences? the instruments have otherwise proved good in very wild changeable weather. Some seamen carry their ideas of lunar influences to an unlimited extent, and they are occasionally referred to by scientific men. I should like to NO. 8,-VOL. XVII.
know through the medium of your Magazine, how far lunar influences are likely to affect the winds, and the action of the barometer.
The action of the barometer within the Tropic of Cancer.—We crossed the tropic at 30° W., and our course trending to the southward to 38° W. AT 22° N., the trade winds south-easterly frequently very light with calms occasionally in the evening. I observed here that the barometer fell from 08 to one-tenth of an inch every afternoon, between noon and 4 P.M., but the rise again was very gradual; it had generally risen half by 8 A.m., and got up by noon to the height which it had fallen from noon height 30.05 inches. Thence to 48° or 49° W.; at 211° N. the winds were E. and E.N.E., more steady and fresher about No. 6; the same action of the instrument continued. But at that point or between 48° and 52° W., the tropic and 20° N. a remarkable baffle took place in the winds, flying about between the N. and S. round by E., in light breezes with calms, (I have twice before experienced the winds westerly in this space at a No. 6 breeze,) both the sea and sky in and after passing this space, thence to the tropic at 60° W., became less tropical. Very perfect and far-spread clouds No. 1, cirrus or curl clouds, with less perfect forms of Nos. 2 to 7 collectively cirrostratus or wave clouds. It occasionally became overcast with showers of rain. The regular action of the barometer ceased, it ranged between 30 and 30:10 inches, but quite irregular, although between 54° and 60° W. the strength and force of the winds were very like the first section between 30o and 38° W: At 26° N. and 62° W. we had the most perfectly formed No. 8 cloud cirrostratus that I ever saw, and with easterly winds light and moderate, we gradually passed into the regular northern sky, sea, &c.
Off Bermuda baulked by north-westerly after strong southerly winds and a dark rainy night, the light excellent: another op St. Davids would make it complete.
The defects which I have here pointed out, I have myself found very detrimental, and as others in the same position may experience the same defects, I trust these remarks may be useful. Should you think them worthy of a place in your valuable journal, from which I have derived much information and amusement, I should feel obliged by their insertion.
RICHARD LEIGHTON, To the Editor N.M.
Commander of the Royal Adelaide.
Pacific NAVIGATION,—From the Sandwich Islands to Valparaiso.*
Extract from the remarks of Mr. H. Thompson, late Master of
(Concluded from page, 342.) The passage from the Sandwich Islands to Valparaiso occupied sixty
*On Sunday October 23rd, 1836 a destructive tempest occurred at Valparaiso. A succession of fine serene days had given promise of the arrival of that season wherein nothing but the usually settled dry weather and customary