Part 9

+-----+-------------+---------+---------+--------------+-------------+ | | | | | [Sun] | | | |Mon. |A.M.| | |Amplitude| | | |Day, | or |Latitude|Longitude|corrected| Ship’s | Magnetic | |and |P.M.| in. | in. |for dip, | head. | amplitude. | |Year.| | | | &c. | | | +-----+-------------+---------+---------+--------------+-------------+ | 1814| | | | | | | | May | | North. | East. | | | | | 11 |A.M.| 53° 38 | 2° 22 | 24° 12 | N.W. |S. 61° 15´ E.| | 12 |A.M.| 54 34 | 2 37 | 23 59 | N.W._b_N. |S. 61 20 E.| | 16 |A.M.| 57 2 | 3 37 | 24 1 | N.N.E. |S. 66 45 E.| | 16 |P.M.| 57 53 | 2 21 | 21 32 | N_b_W.½W. |N. 62 50 W | | 17 |A.M.| 59 4 | 0 32 | 14 42 | N._b_W. |S. 75 20 E.| | 24 |P.M.| 60 27 | 1 58 | 15 21 | N.E._b_E. |N. 50 15 W | | 25 |A.M.| 60 27 | 2 0 | 27 6 | N._b_W. |S. 60 40 E.| | 26 |P.M.| 60 52 | 2 50 | 18 33 | N.E. |N. 58 40 W | |June | | | | | | | 2 |P.M.| 73 14 | 18 10 | 17 50 | N.E._b_N. |N. 60 30 W | | 4 |P.M.| 74 27 | 19 58 | 19 9 | W.S.W. |N. 60 30 W | | 8 |P.M.| 73 59 | 29 55 | 18 20 | N.E._b_N. |N. 66 15 W | | 8 |P.M.| 74 0 | 29 52 | 15 22 | W.S.W. |N. 48 40 W | | 13 |P.M.| 71 10 | 27 10 | 8 52 | S.W.½S. |N. 25 0 W | | 18 |P.M.| 75 22 | 18 21 | 15 2 | N._b_E. |N. 37 50 W | | 26 |P.M.| 78 11 | 6 55 | 20 38 | E.S.E. |N. 55 0 W | |July | | | | | | | | 3 |A.M.| 72 53 | 21 21 | 17 47 | S.S.E. |S. 78 40 E.| | 22 |P.M.| 70 27 | 10 38 | 17 14 | E.S.E. |N. 61 30 W | |Aug. | | | | | | | | 1 |P.M.| 68 58 | 10 25 | 15 26 | W.½N. |N. 52 40 W | | 2 |A.M.| 68 33 | 9 10 | 13 40 | W.½_b_S.S. |S. 79 32 E.| | | | | | | | | | 2 |P.M.| 68 20 | 8 59 | 14 32 | S.S.W. |N. 55 30 W | | 2 |P.M.| 68 20 | 8 59 | 13 50 | West. |N. 51 16 W | | 2 |P.M.| 68 20 | 8 59 | 12 57 | N.E._b_N. |N. 56 20 W | | | | | | | | | 8 |P.M.| 67 37 | 3 20 | 15 6 | South, |N. 57 35 W | | 11 |A.M.| 62 10 | 0 20 | 13 48 | W._b_N. |S. 65 55 E.| | | | | West, | | | | | 14 |A.M.| 61 23 | 0 6 | 20 18 | W.½S. |S. 52 30 E.| | 14 |P.M.| 60 57 | 0 23 | 15 47 | E.S.E. |N. 60 0 W | | 14 |P.M.| 60 57 | 0 10 | 3 00 | W._b_S. |N. 34 30 W | | 15 |P.M.| 60 25 | 0 28 | 11 52 | E.S.E. |N. 62 0 W | | 17 |P.M.| 59 7 | -- -- | 13 23 | W._b_S. |N. 55 30 W | |Sept.| | | West, | | | | | 2 |A.M.| 58 17 | 8 31 | 6 58 | N.W. |S. 61 15 E.| | 2 |A.M.| 58 17 | 8 31 | 8 26 | North. |S. 62 17 E.| | | | | | | | | | 13 |P.M.| 49 59 | 6 22 | 8 12 | S.E._b_E. |N. 71 30 W | | | | | | | | | | 14 |A.M.| 49 6 | -- -- | 19 5 | . . . |S. 46 30 E.| | | | | | | | | | 14 |P.M.| -- -- | -- -- | -- -- | . . . |N. 57 0 W | +-----+-------------+---------+---------+--------------+-------------+

+-----+----------+-------+-------------------------------------------- |Mon. | | | |Day, |Variation.|Differ-| _Remarks, &c. &c._ |and | | ence. | |Year.| | | +-----+----------+-------+-------------------------------------------- | 1814| | | | May | | | | 11 | 24° 49´ W| |Very good sights. | 12 | 26 18 | | -- -- | 16 | 21 35 } | 5° 25| -- -- | 16 | 27 0 } | | -- -- | 17 | 27 40 | | -- -- | 24 | 24 49 | | -- -- | 25 | 24 4 | | -- -- | 26 | 20 14 | | -- -- |June | | | | 2 | 11 35 | |Very good. Sounded 100 fathoms, fine mud. | 4 | 14 28 | |Not very good. | 8 | 4 55 } | 6 25|Very good.} Both sights were equally good. | 8 | 11 20 } | |Very good.} The ship was immediately put on | | | | the other tack. | 13 | 13 10 | |Very good. North Cape N.W._b_W.½W. 5 leagues. | 18 | 16 12 | |Very good. | 26 | 19 6 | |Very good. Ship surrounded with ice. |July | | | | 3 | 9 22 | |Very good. | 22 | 16 6 | |Very good. |Aug. | | | | 1 | 26 42 | |Very good. Ship some motion. | 2 | 25 14 | |Very good. | | | | | 2 | 22 4 } | |All these sights were equally good. The evening | 2 | 25 11 } | 7 37| was remarkably fine, with a light air from the | 2 | 17 34 } | | S.E. The first set was taken with the ship’s | | | | head S.S.W.; 2d set at West; and 3d set at | | | | N.E._b_N. The ship was put round in this | | | | manner for the purpose. | 8 | 26 43 | |The mean of six sets all good. The weather calm | | | | and fine. | 11 | 31 15 | |The mean of two sets ship steady. Longitude | | | | obtained by [sun], [moon], and chronometer. | 14 | 30 36 } | 5 8|Very good. | 14 | 25 28 } | |Very good. North end of Shetland, S. 11° E. | | | | 5 or 6 leagues. | 14 | 30 40 } | 10 25|Very good. North end of Shetland, S. 48° W. | | | | 4 or 5 leagues. | 15 | 20 15 } | |Very good. Outer Skerry, Shetland, S.S.W. | | | | 2 miles. | 17 | 30 32 | |Very good. Lamb Head, Orkneys, W.½S. 4 or | | | | 5 miles. |Sept.| | | | 2 | 33 1 } | |Both these sights were good, and the ship was | 2 | 29 31 } | 3 30| put on the courses, as given purposely. St. | | | | Kilda Island S. 9° W. 8 or 9 leagues. No | | | | soundings at 180 fathoms. | 13 | 22 30 | |At anchor in St. Mary’s. St. Agnes’s | | | | Light-House W. 54° S. Castle E. 51° S. | 14 | 27 16 | |This azimuth was taken on shore at St. Agnes’s | | | | Light-House, with false horizon. | 14 | 27 31 | |This amplitude was taken on shore at St. Mary’s | | | | flag-staff.--Most excellent. +-----+----------+-------+--------------------------------------------

[Transcriber's Note: The table was laid out in the original with the data on one page and the Remarks on the next, this table has been divided to fit the page constraints. The date column has been repeated for ease of reference. [sun] and [moon] are represented by symbols in the original.]

No. IV.

In the Appendix to the second volume of Flinders’ Voyage, which has lately been published, there is an article of considerable length and ability, on the Variation of the Compass. In that article, the observations made by that excellent sailor, corroborate, in a remarkable degree, and accord with those made in the Sybyll. I have selected a few of the most decisive instances.

+---------+----------+---------------+----------+------------+-------+ | 1802. | Lat. | Long. | Course. | Var. | Diff. | +---------+----------+---------------+----------+------------+-------+ | April | | | | | | |22. A.M. | 39° 38´S.| 141° 40´E. az.| W.S.W. | 11° 52´E. }| | |24. | 39 38 | 144 1 | S. | 7 59 }| 3° 53´| | July | | | | | | |15. P.M. | 34 5 | 135 9 | S.E._b_E.| 1 33 W. }| | |-- | 34 6 | 135 9 ampl. | S.W._b_W.| 3 56 E. }| 5 39 | |28. | 25 0 | 153 23 | N.W._b_N.| 9 39 }| | |29. | 24 43 | 153 27 | S.E.½S. | 6 33 }| 3 6 | +---------+----------+---------------+----------+------------+-------+

After such a coincidence, the fact of the variations depending greatly on the ship’s course cannot possibly be called in question; though it is certainly surprising that it has not been sooner attended to in the way that it deserves, by other navigators; for it did not altogether escape their observations. Mr. Wales, astronomer to Captain Cook’s ship, the Resolution, had made the same observations in a pretty accurate manner; and M. Entrecasteaux, though without assigning any cause, says, that the “Compass showed differences of several degrees in variation at sea, though observed with the greatest care, and within the space of a few minutes.”

After a more enlarged series of observations shall have been taken, and after the attention of astronomers is directed to this fact, we may confidently expect a most important improvement in the science of navigation.

No. V.

The following article, “ON THE TREMENDOUS CONCUSSIONS OF THE FIELDS OF ICE,” in the Arctic Sea, is extracted from Mr. Scoresby’s valuable Memoir on “Polar Ice” in the Wernerian Society’s Transactions.

“The occasional rapid motion of fields, with the strange effects produced on any opposing substance, exhibited by such bodies, is one of the most striking objects this country presents, and is certainly the most terrific. They not unfrequently acquire a rotatory movement, whereby their circumference attains a velocity of several miles per hour. A field, thus in motion, coming in contact with another at rest, or more especially with a contrary direction of movement, produces a dreadful shock. A body of more than ten thousand millions of tons in weight,[38] meeting with resistance, when in motion, the consequences may possibly be conceived!

[38] A field of thirty nautical miles square surface, and thirteen feet in thickness, would weigh somewhat more than is here mentioned. Allowing it to displace the water in which it floats, to the depth of eleven feet, the weight would appear to be 10,182,857,142, nearly in the proportion of a cubic foot of sea water to 64 lbs.

“The weaker field is crushed with an awful noise: sometimes the destruction is mutual. Pieces of huge dimensions and weight are not unfrequently piled upon the top, to the height of twenty or thirty feet, whilst doubtless a proportionate quantity is depressed beneath. The view of those stupendous effects in _safety_, exhibits a picture sublimely grand, but where there is danger of being overwhelmed, terror and dismay must be the predominant feelings. The whale-fishers at all times require unremitting vigilance to secure their safety, but scarcely in any situation, so much as when navigating amidst those fields. In foggy weather they are particularly dangerous, as their motion cannot then be distinctly observed. It may easily be imagined, that the strongest ship can no more withstand the shock of the contact of two fields, than a sheet of paper can stop a musket ball. Numbers of vessels, since the establishment of the fishery, have been thus destroyed. Some have been thrown upon the ice; some have had their hulls completely torn open; and others have been buried beneath the heaped fragments of the ice.

“In the year 1804, I had a good opportunity of witnessing the effects produced by the lesser masses in motion. Passing between two fields of bay-ice, about a foot in thickness, they were observed rapidly to approach each other, and before our ship could pass the strait, they met, with a velocity of three or four miles per hour; the one overlaid the other, and presently covered many acres of surface. The ship proving an obstacle to the course of the ice, it squeezed up on both sides, shaking her in a dreadful manner, and producing a loud grinding, or lengthened and acute tremulous noise, accordingly as the degree of pressure was diminished or increased, until it had risen as high as the deck. After about two hours, the velocity was diminished to a state of rest; and, soon afterwards, the two sheets of ice receded from each other nearly as rapidly as they had before advanced. The ship, in this case, did not receive any injury; but had the ice been only half a foot thicker, she would probably have been wrecked.

“In the month of May of the present year (1813) I witnessed a more tremendous scene. Whilst navigating amidst the most ponderous ice which the Greenland seas present, in the prospect of making our escape from a state of _besetment_, our progress was unexpectedly arrested by an isthmus of ice, about a mile in breadth, formed by the coalition of the point of an immense _field_ on the north, with that of an aggregation of _floes_ on the south. To the north field we moored the ship, in the hope of the ice separating in this place. I then quitted the ship, and travelled over the ice to the point of collision, to observe the state of the bar which now prevented our release. I immediately discovered that the two points had but recently met; that already a prodigious mass of rubbish had been squeezed upon the top, and that the motion had not abated. The fields continued to overlay each other with a majestic motion, producing a noise resembling that of complicated machinery, or distant thunder. The pressure was so immense, that numerous fissures were occasioned, and the ice repeatedly rent beneath my feet. In one of the fissures, I found the snow on the level to be three and a half feet deep, and the ice upwards of twelve. In one place, hummocks had been thrown up to the height of twenty feet from the surface of the field, and at least twenty-five feet from the level of the water; they extended fifty or sixty yards in length, and fifteen in breadth, forming a mass of about two thousand tons in weight. The majestic unvaried movement of the ice--the singular noise with which it was accompanied--the tremendous power exerted--and the wonderful effects produced--were calculated to excite sensations of novelty and grandeur, in the mind of even the most careless Spectator!

“Sometimes these motions of the ice may be accounted for. Fields are disturbed by currents--the wind--or the pressure of other ice against them. Though the set of the current be generally towards the south-west, yet it seems occasionally to vary; the wind forces all ice to leeward, with a velocity nearly in the inverse proportion to its depth under water; light ice consequently drives faster than heavy ice, and loose ice than fields: loose ice meeting the side of a field in its course, becomes deflected, and its re-action causes a circular motion of the field. Fields may approximate each other from three causes: _First_, If the lighter ice be to windward, it will, of necessity, be impelled towards the heavier; _secondly_, As the wind frequently commences blowing on the windward side of the ice, and continues several hours before it is felt a few miles distant to leeward, the field begins to drift before the wind can produce any impression on ice, on its opposite side; and, _thirdly_, Which is not an uncommon case, by the two fields being impelled towards each other, by winds acting on each from opposite quarters.

“The closing of heavy ice, encircling a quantity of bay ice, causes it to run together with such force, that it overlaps wherever two sheets meet, until it sometimes attains the thickness of many feet. Drift ice does not often coalesce with such a pressure as to endanger any ship which may happen to be _beset_ in it: when, however, land opposes its drift, or the ship is a great distance immured amongst it, the pressure is sometimes alarming.”

No. VI.

_On the approximation towards the Poles, and on the possibility of reaching the North Pole. From Mr. Scoresby’s paper in the Wernerian Society’s Transactions._

“We have already remarked, that the 80th degree of north latitude is almost annually accessible to the Greenland whale-fishers, and that this latitude, on particular occasions, has been exceeded. In one of the first attempts which appears to have been made to explore the circumpolar regions, in the year 1607, Henry Hudson penetrated the ice on the north-western coast of Spitzbergen to the latitude of 80° 23´ N. In 1773, Captain Phipps, in “a voyage towards the North Pole,” advanced, on a similar track, to 80° 37´ of north latitude. In the year 1806, the ship Resolution of Whitby, commanded by my father, (whose extraordinary perseverance and nautical ability are well appreciated by those in the Greenland trade, and proved by his never-failing success,) was forced, by astonishing efforts, through a vast body of ice, which commenced in the place of the usual _barrier_, but exceeded its general extent, by at least a hundred miles. We[39] then reached a navigable sea, and advanced without hindrance, to the latitude of 81½ north, a distance of only 170 leagues from the pole; which is, I imagine, one of the most extraordinary approximations yet realized.”

[39] “I accompanied my father, on this voyage, in the capacity of chief mate.”

* * * * *

“The southern hemisphere, towards the pole, was explored by Captain Cook, in various meridians, and with indefatigable perseverance. In his first attempt, in 1772, they met with ice in about 51° south, and longitude 21° east. They saw great fields in 55° south, on the 17th of January, 1773, and, on February the 24th, were stopped by field-ice in 62° south latitude, and 95° east longitude.

“Again, on the second attempt, in December of the same year, they first met with ice in about 62° south latitude, and 172-173° west longitude; and on the 15th, saw field-ice in 66°. On the 30th January, 1774, they were stopped by immense ice-fields in latitude 71° 10´ 30´´ and 107° west longitude, which was the most considerable approximation towards the south pole that had ever been effected.

“Thus, it appears, that there subsists a remarkable difference between the two hemispheres, with regard to the approach of the ice towards the equator; the ice of the southern being much less pervious, and extending to much lower latitudes than that of the northern hemisphere.

“That the 73d or 74th degree of north latitude can be attained at any season of the year, whereas the 71st degree of south latitude has been but once passed.--And,

“That, whilst the antarctic _ne plus ultra_ appears to be the 72d degree of latitude, that of the arctic extends full 600 miles farther; the nearest approach to the southern pole being a distance of 1130 miles, but to the north, only 510 miles.

“With regard to the probability of exploring the regions more immediately in the vicinity of the pole than has yet been accomplished, or even of reaching the pole itself, I anticipate, that, without reference to the reasoning on which the opinion is grounded, it might be deemed the frenzied speculation of a disordered fancy. I flatter myself, however, that I shall be able to satisfy the Society, that the performance of a journey over a surface of ice, from the north of Spitzbergen to the pole, is a project which might be undertaken, with at least a probability of success.

“It must be allowed, that many known difficulties would require to be surmounted--many dangers to be encountered--and that some circumstances might possibly occur, which would at once annul the success of the undertaking. Of these classes of objections, the following strike me as being the most formidable, which, after briefly stating, I shall individually consider in their order.

1. The difficulty of performing a journey of 1200 miles, 600 going and 600 returning, over a surface of ice--of procuring a sufficient conveyance--and of carrying a necessary supply of provisions and apparatus, as well as attendants.

“The difficulties may be increased by

(_a._) Soft snow; (_b._) Want of continuity of the ice; (_c._) Rough ice; and (_d._) Mountainous ice.

“2. The difficulty of ascertaining the route, and especially of the return, arising from the perpendicularity of the magnetical needle.

“3. Dangers to be apprehended,

(_a._) From excessive cold; (_b._) From wild beasts.“

“4. Impediments which would frustrate the scheme;

(_a._) Mountainous land; (_b._) Expanse of sea; (_c._) Constant cloudy atmosphere.

“1. It is evident that a journey of 1200 miles, under the existing difficulties, would be too arduous a task to be undertaken and performed by human exertions alone, but would require the assistance of some fleet quadrupeds, accustomed to the harness.

“Rein-deer, or dogs, appear to be the most appropriate. If the former could sustain a sea-voyage, they might be refreshed in the northern part of Spitzbergen, which affords their natural food. They could be yoked to sledges framed of the lightest materials, adapted for the accommodation of the adventurers, and the conveyance of the requisites. The provision for the adventurers, for compactness, might consist of portable soups, potted meats, &c. and compressed lichen for the rein-deer. The instruments and apparatus might be in a great measure confined to indispensables, and those of the most portable kinds; such as tents, defensive weapons, sextants, chronometers, magnetic needles, thermometers, &c.

“As the rein-deer is, however, a delicate animal, difficult to guide, and might be troublesome if thin or broken ice were required to be passed; dogs would seem, in some respects, to be preferable. In either case, the animals must be procured from the countries wherein they are trained, and drivers would probably be required with them. The journey might be accelerated, by expanding a sail to every favourable breeze, at the same time, the animals would be relieved from the oppression of their draughts. It would appear, from the reputed speed of the rein-deer, that, under favourable circumstances, the journey might be accomplished even in a fortnight, allowing time for rest and accidental delays. It would require a month or six weeks with dogs, at a moderate speed; and, in the event of the failure of these animals on the journey, it does not seem impossible that the return should be effected on foot, with sledges for the provisions and apparatus.

“(_a._) Soft snow would diminish the speed, and augment the fatigue of the animal; to avoid which, therefore, it would be necessary to set out by the close of the month of April, or the beginning of May; or at least, some time before the severity of the frost should be too greatly relaxed.

“(_b._) Want of continuity of the ice would certainly occasion a troublesome interruption; it might nevertheless be overcome, by having the sledges adapted to answer the purpose of boats[40]; and it is to be expected, that although openings amidst the ice should occur, yet a winding course might in general be pursued, so as to prevent any very great stoppage.

[40] The sledges might consist of slender frames of wood, with the ribs of some quadruped, and coverings of water-proof skins, or other materials equally light.