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Centre and join them as before; repeat this Operation six or seven Times, taking Care not to put the Magnets out of their Parallelism, and the Needle will be sufficiently Magnetical.
The Method of Keeping a Journal at Sea.
Y keeping a Journal, is meant keeping such an Account of the Ship’s Way that the Mariner may be able at any Time to ascertain the Latitude and Longitude the Ship is in ; it therefore should be the great Concern of every Person who takes upon him the navigating of Ships to remote Parts, to be expert therein, as the Lives and Fortunes of so many Men are committed to his Charge. wi. à Ship is bound from one Place to another, which lies so far from her, that she is obliged to go out of Sight of Land for any considerable Time, as from England to Jamaica; at the Time of her leaving Sight of Land, she is said to take her Departure, and that Part of the Land she then leaves, is said to be the Place she takes her Departure from ; such as the Land's End, Lizard, &c. and at the Time of taking such Departure, the Captain or Mate generally takes the Bearing and Distance of that Land (according to his Judgment) and sets it down on the Log-board, or in the Log-book against the Time it was taken, thus, Land's End N. N. E. Dist. 7 Leagues, or Lizard N. by W. Dist. 5 Leagues, &c. In the same Manner may the Departure from any Place be taken, as may be seen in the first Day's Log. of the following Journal, where the Log book is marked in Columns for Hours, Knots, Fathoms, Courses, Winds, Leeway, Transačtions; and under it the Columns for Courses, Distances, Northings, or Southings, Eastings, or Westings, the Latitude by Dead Reckoning, Latitude by Observation, Meridian Distance, Difference of Longitude, Longitude in, and in the last, Bearing and Distance of the Land. Notice must be taken, that in the Column for Course, you are always to set down the Course you have made by your Reckoning for that 24 Hours; that is, from the Noon of the Day before to the Noon of the Day you work on, the Sea Account being always kept from Noon to Noon. In the Columns for Distance you are to set down the Distance made by your Reckoning for that 24 Hours. In the Columns of Northing and Southing, you are to set down the Difference of Latitude made in that 24 H. marking the Column with North, if the Difference of Latitude be North; and South, if South. so In
7thly. If the Ship tries under the Mizen only, her Way is about two Points before the Beam ; that is, allow six Points for her Leeway. 8thly. When she lies a Hull, that is, with all her Sails furled, her Way is one Point before the Beam, and then seven Points is her Leeway. 9thly. When a Ship is lying-to under a Main-sail, Mizen, &c. then observe how she comes up and falls off, and take the Middle between the two Points, and from that allow the Leeway and VaIIatl Orl. Not E. In all Cases, Respect must be had to the Smoothness of the Water, or to the Sea’s running high, the Mould and Trim of the Ship, and then the Allowances may be ascertained with the greater Certainty, by setting the Ship's Wake by a Compass placed on each . of the Ship's Quarter, which is usually set there for that Purpole. For it is well known, that some Ships, with the same Quantity of Sail, and with the same Gale, will make more or less Leeway than others; and also the same Ship when she is out of her Trim, or differently loaded, will make different Leeways; for it is observable, that the more Water a Ship draws, the less Leeway she makes ; because she then meets with a greater Resistance in splitting the Water with her Side, than otherwise she would. The Leeway may be easily found by the Azimuth Compass, by turning the Instrument about until you see the Wake of the Ship either over the Sights, or parallel to them ; then the Point of the Card, which is cut by the vertical Line in the Box, which is nearest to you, is the true Course; the Difference between that and the Course given by the Compass in the Bittacle, is the Leeway reQuired, which ought to be accordingly entered upon the Ło. board. There is another Way of finding the Leeway, by fixing a Compass cut in Lead (or in other Metal) on the Poop, or some other convenient Part of the Ship's Stern, with the Meridian parallel to the Ship's Side, and in the Centre a Pin is fixed, to which is fastened a small Line of a good Length, with a Piece of Wood at the End of it, that it may be dragged after the Ship. The Point or Degree cut by this Line will shew the Leeway; if it cuts the Meridian the Ship makes no Leeway; but if it does not, the Difference between the Meridian and where it cuts is the Leeway. By some of the above Methods, the Leeway (if there be any) ought to be carefully observed as often as may be judged necessary 3, and these Observations should be punétually set down by the Officer of the respective Watch ; at least, if no Observation be made, he ought to set down the Leeway according to his Judgment once or twice in the Watch, and by this Means the Course made good may e found to a much greater Certainty and Exačtness than by the common Method of allowing for Leeway, when the Day's Account comes to be worked, (which is generally once in 24 Hours:) For all
an Observation must certainly be better than any Guess. But if no Observation be made, the Person who is upon Deck, and has the Care of the Watch, is better able to make proper Allowances, while Things are fresh in his Memory, and while he is an Eye Witness of the several Accidents that happen; and certainly much more capable than another who was not upon Deck during the whole Watch. - I have often admired to see how particularly every Thing is stated upon the Log-board, excepting the Leeway; and yet that (which is one of the most material Articles, since the Course, according to the Compass, must be correćted by it) only allowed for the next Day, according to every one's Fancy, thereby, as it were, keeping as many different Journals as there are Artists (so called) on board the Ship, and yet not one regular Journal properly kept amongst them all, since one of the most material Articles is only guessed at.
Leeway and Variation, when they are both to be allowed one
Way, that is, both to the Right Hand, or both to the Left, add them together, and allow their Sum the same Way they were to be
allowed. But if they are to be allowed, one to the Right Hand, and the other
to the Left, subtract the less from the greater, and allow the Remainder the same Way the greater was to be allowed.
erly Variation; I would know my true Course :
Leeway to the Left Hand I Point.
Their Sum to be allowed to the Left Hand I # whence
Leeway to the Right Hand 2 # Points. Variation to the Left Hand 1 # Points. The Rem. to be allowed to the Right Hand 1 # whence