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Cummins's Mineral Stmpiesometer U an invaluable instrument to the mariner, as well as for mountain purposes. The fluid will retail) ita colour, cannot evaporate, neither will it congeal at a low temperature; the instrument is admirably adapted for carriage, it being very portable: is ready for use in a moment, without requiring any preparation; and is stated to be superior to any portable barometer yet invented. Another great advantage of it is, that the fluid is preserved without the assistance or inconvenience of a cork stopper, as in other instruments of the kind.
Channel Packet Station.—Dartmouth and Falmouth.
Sir.—As you have published the Report of the Commissioners appointed to decide on the comparative merits of the ports in the Channel, with reference to a Steam Packet Station, in your magazine, I am sure you will not object to call the attention of the authorities, and of the Commissioners themselves, to an error in their calculations, which may have materially influenced their decision.
As regards safety, they do not consider Dartmouth to be superior to Falmouth; they allow that Falmouth is provided with a lighthouse, buoys, &c, which must all be done at Dartmouth, at great expense, if the Packets are moved there; but they consider that a gain of two hour* in time, warrants the change and the attendant expenses. The following is their statement of the relative distances of Falmouth and Dartmouth.
"If to Falmouth we subtract a difference in the sea distance of 47 miles, or in time six hours, and add 82 miles mail coach, or in time eight hours, leaves in favor of Dartmouth two hours"
Now that they have made a very great mistake in their mail coach distance a reference, to any road book will show. They calculate all their distances on the West of England to Exeter, through which city all the roads run. The old post-office distances are as follows :—
Exeter to Falmouth . . 101 miles
Do. Dartmouth . . 35
Difference .... 66
The modern roads make the distances
Kxeter to Falmouth . , 97
Do. Dartmouth . . 33
Difference .... 64
The Dartmouth distance can be reduced to thirty miles, if a new road is cut; but even then, the difference will be only sixty-seven miles, making an error of fifteen miles, or one hour and a half in time, in the calculation of the Commissioners, and leaving a difference of time in favor of Dartmouth of half an hour only, which half hour depends on the steamers always making eight miles an hour in all weathers, which it is well known they cannot do.
It certainly is worth considering again, whether for a doubtful half htar it it worth depriving a town of an old-established benefit, and going to the expense which must be incurred to make Dartmouth afe. I am, Sir, &c,
Totness, 26th Nov. An Old Subscriber.
Lo-s or The Buffalo Store Ship—This ship was at anchor in Mercury Bay, New Zeeland, on the 28th of July, on which day it came on to blow a most powerful gale, and continued so for three days. Every preparation was made for encountering it by striking loweryards, topmasts, and letting go all the anchors; but, notwithstanding all these precautions, the ship parted from them, and by the coolness and good management of her commander, Mr. J. Wood, she was run ashore, and all her crew saved, with the exception of one poor unfortunate seaman, named Moore, and a boy by the name of Comes, both belonging to Chatham. The ship is now high and dry at low water, on the beach, and is completely gone to pieces; and the crew were folly employed in saving what stores and provisions they could from the wreck. A great portion of the ship's company was at the time in the woods, cutting and transporting timber; but on hearing of the loss of the ship, they went from Cooks Bay in an open boat, to the assistance of their shipmates, and in doing this they met with most severe weather, and were compelled to run into a creek to ride out a gale. At the date of the information, August the 6th, a ship was standing into Mercury Bay, to convey the officers and crew who had been encamped on the beach to Sydney, whence they would come to England. —Hampshire Telegraph.
Low Of The Spf.y Packet.—Accounts have been received of the wreck of the Spey packet, Lieut. James, on her voyage to Havana, on the 21th of November last. The Spey, it appears, intended crossing the tail of the (Treat Bahama Bank, passing on it between Racoon Cay and Bonavista Cay, through an opening which had not fallen under the examination of our surveyors, instead of passing to the southward. Going at the rate of five knots, she was too fast on the reef to be got off with the utmost exertions of her crew. Happily no lives were lost, and, indeed, everthing of importance in the vessel was saved by the judicious and active measures of her commander.
Wecan assure our readers that they will find Poor Jncka very pleasant Nautical companion, steering his course of duty through the sea of life beset with dangers and difficult navigation, starting from port in an obscure station, but by a careful attention to the helm and trimming his sails by the help of good advice and good example, he returns home to reap the fruits of honesty and good conduct.
Patch-Work—By Captain Basil Hall, R.—N.Moxon, London, 1841.
The high reputation of Captain Hall, which his peculiar style has long ago obtained for him as a Naval writer, is well sustained in the three very interssting volumes before us. 'Iliere is indeed in them something of everything, every hue and colour of shreds and patches, but all forming a delightful and ■nd pleasing collection. We have not room to particularize, but (hall match ■ leaf out of the Captain's book on gome not distant occasion, and in the mean time recommend those who enjoy cheerful and animated pictures in narrative* and descriptions to have immediate recourse to Patch work.
Sermons.—By the Rev. W. liennet, vol. 2.—Cleaver, London.
We do not sit in judgment on these matters, but having already recommended the first volume to our Naval friend*, and finding the second no less to our own taste, we may say to them, "you may gain instruction from its pages, and rejoice over the ' message' it contains."
Picturesque Views On The River Nioer.—Sketched during Lander's latt visit in 1832 and 1833.—% Commander W. Allen, R.N., F.R.Q.S., &e.
And sketched we may add with great taste.
There is a charm about these views imparted to them by the artist, and the subject which is particularly captivating. It is impossible to look them over but with feelings of deep interest, excited by reflections on the benighted condition of the African race, who, in the midst of the profuse luxuriance which Nature has bestowed on a large portion, (if she has been niggardly in other parts) of their country, are still the victims of blind superstition, ignorance, and barbarism. The views are done in the best style of the lithography of the present day, and form a be-fitting ornament to the drawing-room table.
The Friend Of Africa.
This little periodical which appears to have been got up for the express purpose of announcing the progress of the civilization of Africa, gives a full account of the expedition about to sail for the Niger,' and which we shall avail ourselves of in our next number. The opening address makes a strong appeal to its readers, and the small sum of one penny per week should carry it far and wide. There seems to be every probability of finding in it the latest intelligence of the expedition, as well as the most interesting accounts from central Africa.
The Practice Of Navigation And Nautical Astronomy.—By II. Raper, Lieut. R.N., Secretary to the Royal Astronomical Society.—Rale, London. 1840.
(Continued from p. 895 of vol. for 1840.)
The work before us commences with an introductory chapter, in which many elementary matters are explained, as are required by those who have only an acquaintance with the first rules of arithmetic. Passing over other matter, we would direct particular attention to the manner in which the raising of the trigonometrical canon is trented. The method used is simpler, easier, and will be better remembered, than what we find in the common books of navigation, where the student is directed to compare the side made radius to radius, an angle, to a side and vice versa. Here it is first shown under the head proportions,—how when four terms are proportional, three being given, the fourth may be found. The true nature of the trigonometrical canon being then demonstrated by referring to similar triangleB, and the method of employing rightly the terms sine, co-sine, tangent, fire, being shown in a way that cannot well be misunderstood, it becomes almost impossible if the slightest attention has been paid, for the learner not to be now enabled to raise and solve the canons in the natural and legitimate manner, by comparing a side to a side, &c. We are not aware, that in all our reading we ever saw a subject better explained, and it is done too without any reference to pure mathematical knowledge. After having acquired this method, the common one which is generally given becomes very easy, and is likewise in a few words described to the reader. There now follows a passage in which the two methods are compared together, which we shall insert, not only as a specimen of the author's style, but to show what care is taken that nothing may be misunderstood, by those who have not the advantage of an instructor.
"Now, in the first place, the method proposed is more natural than the latter, because, when the two sides are taken together, their trigonometrical relation to each other is immediately perceived, which, when they are separate is not so apparent. Again, since the term sine or cosine is determined altogether by that side which we make radius, the term radius should, according to the natural progress of ideas, immediately precede the term sine, cosine, &c."~ page 28.
After this introductory chapter, we come to what may be considered more peculiarly the object of this treatise. In general the cases into which the dinertot sailings may be divided, are used merely as a vehicle for exercising the learner in plane trigonometry. That error has been avoided here, as every example which is given in the chapter which explains these matters, is a useful problem in navigation. We must not, however, thus hastily dismiss that part which treats of what is usually called great circle sailing. Most mariners are aware that this method alone gives the proper courses to be steered, in order to make most directly to any distant port to which the vessel may be bound ; butit •Uoshews something more. By this sailing, it may be ascertained how fur a ship may deviate from her apparent direct course, in search of a wind, or from any other cause, without increasing the number of miles that she has to run, in order to reach her destination. Highly useful as this method of navigation appear*, tt has hardly ever been practiced, owing to the complicated form in which the rules hare been laid down! Kerigan in his laborious work on navigation, published in 1826, has attempted to simplify the rules, but the directions which he fives are of too complicated a nature to be followed by the generality of seamen. n the work before us, all these difficulties are completely mastered, and great circle sailing is now rendered almost as easy as Mercator's. The plan which Lieutenant Raper adopts for solving the different cases by inspection is very short, and will be the method commonly used at sea. This is effected by a new and original table devised by himself, and will be hereafter of the utmost importance in the science of navigation. Without entering into any lone account of this table, we shall only generally state, that by its aid spherical triangles can be solved much in the same manner, that plane right-angled triangles may be solved by the aid of what is commonly called the traverse table.
After the sailings, we have an excellent and original chapter on taking departures, in which the most accurate and useful methods of ascertaining distances from the land are clearly explained.
In that portion of the work which treats of nautical astronomy, no rule is omitted for any possible case that may occur, and the work concludes with a chapter explanatory of the proceedings that are necessary for the safe navigating of a ship; in short, pointing out the best manner of making a practical application of all the matters which have been previously treated.
Many of the tables are quite original. Table 3, which is entitled spherical traverse table, we have already alluded to as performing for spherical triangles all that the present common traverse table does for right angled triangles. This table will no doubt be very soon extensively used, more particularly if the author performs his promise of publishing it separately in a more extended form. After the logarithmic sines, &c, is given a table for interpolation, by which the seconds if required may be taken out at once. Table 61 is the log. sine square calculated to fifteen seconds of space, and six places of logarithms, and is used in all the rules given in nautical astronomy, the answer being always to be found in this table. All the tables used in clearing the lunar distance are so arranged, that allowance may either be made or omitted for the height of the barometer and thermometer. But it would be only trying the patience of the reader to proceed further, therefore, the last table to which we shall refer, is that containing maritime positions, although not placed last in this work, as it wmes in its natural and legitimate order, immediately after the table of meridional parts. It has been too much the practice for authors to compile this table, principally from such books of navigation as have preceeded their own,
ENLARGED 8ERIE8 NO. 2 VOL. FOR 1841. T
not paying mfficient attention to the longitudes more accurately ascertained, aud to be found inserted in Foreign and English sailing directions;—in the proceedings of the geographical society, in the pages of this journal, or occasionally only in manuscript, either at the hydrographical office, or in the possession of individuals. But we are happv to find this is far from being the case here. We have carefully examined Lieutenant Rapcr's table, and it appears to us, to have been mainly compiled from those vcrv sources of information to which we have already alluded, sources which have hitherto been too much neglected; in short, we may consider, that we have a compendium of what is actually known on this subject, so that we have now a starting point to go from in the> future attempts that may be made, to determine with greater accuracy the longitudes of maritime places.
But we have other matters pressing on us for attention, and we must again defer the remainder of our notice of this valuable work for another number.
NEW CHARTS. (Published by the Admiralty.) The Natuna Islands—Surveyed by M. E. Paris, in the Corvette La Favorite, commanded by M. La Place.—1831. _
With this chart, a ship may approach the islands in any direction with confidence to within a few miles; indeed, we consider it an in-lispcnsible accompaniment to Horsburgh's account of the islands, as there are several minor points in which the two authorities differ in some degree, and one or two dangers appear that are not alluded to by Horsburgh. The Strait or Malacca—Western Part.
A neat useful sailing chart,—the authorities for which appear to be for the Coast of Sumatra, Lieutenants W. Rose, and R. Moresby, the Strait of Calain, Capt. W. F. W. Owen, Rn., Penang Island and Strait, Lieut. T. Woore, Rn., the Arroa Islands and North Sands, Capt, D. Ross, of the Bombay Marine, and the whole adapted to the valuable Directory of Capt. Horsburgh. The Strait Of Malacca.—Eastern Part.
A similar neat chart; the authorities as before stated: the Siac river and the Straits adjacent to it forming a prominent feature. The Arboa Islands With The North Sands And Calam Strait.
Shewing on an enlarged scale the navigable approaches to these dangers, and a useful chart to vessels availing themselves of the advantage of entering the Malacca Strait by the secure passage afforded by the Calam Strait. The Bashee And Bintano Channels.
We congratulate our seamen, on having thus in a convenient and useful form even the meagre results of navigators as long as they are carefully digested.
This chart we find which is most important, as shewing the high road between Formosa and the Phi Hi pine Islands, has been constructed from loose and conflicting authorities, as is shewn by its unfinished appearance, hut great pains have been taken to render it as useful as possible, and it is decidedly more correct than any former publication of this part.
Promotions And Appointments.
PROMOTIONS. Lieutenants—J. E. F. Risk, com
mission dated November 6th, 1840, to
Captain—R. Shepheard Triscott. stand next in seniority to R. White.
Commander—T. H. Holman. J. H. Woolward, the Hon. G. D. Keane,
Lieutenant—J. Allen, (u). C. R. Carter, commission dated Novem
(The above are the annual coast guard ber 6th, 1840, and to stand on the list
promotions.) for seniority immediately after F. H
Commanders—A. Murray, (b) and Stanfell. L. G. Heath, for passing best
B Duncan, commissions dated Novem- examination at the Royal Naval Col
bsr 4th, 1840. leg8. ,