The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

above factors may be used in,,its stead. cy _ THE COMBINATION BEARING, The combination of the 2-point and 4-point bearing is without doubt the best of the bearing methods, and its great advantage is that it can be solved mentally. What. master is there but what has had the experience of being required to leave the bridge in a rain or snow storm to wrestle with the chart and parallel rulers and - dividers, in plotting the position 'of the vessel, because he was not ac- quainted with methods which do not necessitate such proceedings. WHERE THE BEARING Ig DEFECTIVE. Although the 4-point bearing meth- od alone is defective in one respect, namely, that the navigator sometimes requires to know the distance he is ~ going to pass off the object before it comes abeam, without going to the trouble of finding his position on the chart and laying off the course that will take him the required distance; by using the 2-point method in con- junction with it it serves the purpose admirably. o THE "DODGES" BEARINGS. ' The 2, 3, 5, ete., point bearings and fractional points thereof are sometimes called the "Dodges" by the navigator. The following are a few examples for practice: - You are steering W14S, logging 14 mates an our. At 9:22 Seul Choix Pt. lighthouse bears WNW and at 9:30 the same _ lighthouse ~ bears NW14N. How far and in which di- rection are you from the lighthouse? What kind of a bearing is this? -- HOW IT IS WORKED, This is a 2% point bearing, because this is the number'of points between the course and first bearing; also by doubling the difference between course and first bearing produces the second eine The ship is 28 miles SES from the lighthouse; found thus, the time between bearings is 12 minutes, that is, it took 12 minutes to double the difference in points between course and first bearing; we then have this~ proportion: As 60 minutes, the num- ber of minutes in one hour, is to 12 minutes, the length of time that the vessel has run between bearings at the rate of 14 miles an hour, so is 14 miles to x miles, the unknown quantity to be found, or thus: 60 mins. :12 mins. :: 14 miles : x miles 14 48 12 60) 168.0(2.8 120 'THE Marine ReEvIEw "Votiet ad 19 HVA es AA ite Lee 480 nt se EG fee - 480 x equals 2.8 miles, the distance run between bearings, consequently, it equals the distance the ship is from the light. TO TELL OF THE KIND OF BEARING, Note.--The first thing to be done by the student in working these bear- ing examples is to see what the dif- ference is between course and first bearing; also the difference between first and second bearing. This -will tell you at once what kind of a bear- ing you have to deal with. If there is the same difference between course and first bearing as there is difference between first and second bearing, you know that two of the angles are equal, and that opposite these angles will be found equal sides. Ex.--You are steering N by EXE at the rate of 11% miles per hour. At 4:12 Cana Island lighthouse bears NW and at 4:28 the same lighthouse bears NNW34W. How far and in which direction are you from the lighthouse? oe This is a 2%4-point bearing. The vessel is three miles SSE%E of Cana Island lighthouse; found thus, 60m. l6m, 32 125 mils? nis. and'x equals three miles. A GOOD PRACTICE, Note.--One of the best practices for the student is to plot these bearings On the chart just as they are given here, and over the various lighthouse and points mentioned. This will give him a better idea of their solutions, and will not only prove his work, but will help him to form the right con- ception of the manner in which it is and 'should be done. Always lay off the bearing lines first, and the dis- tance run prick off with the dividers from the chart scale. A good prac- tice is to take the distance off at sec- ond bearing between the dividers, and with one leg of the instrument on the object, let the other come on the line drawn to represent the second bear- ing, mark its place, or keep the point of the dividers there and move the other leg from its position over the object, to where it will exactly meet the line drawn to represent the first bearing. The position of the dividers now represents the course as steered, for on drawing a line connecting these points, and then transferring this. line by means of the parallel ruler to the nearest diagram compass will verify it. Tt you are careful in drawing the lines and measuring the distances, your work will stand cor- rect. These same bearing lines can be laid down by means of the protrac- tor,,on.ajsheet of paper to any de- sired scale. If a large scale is de- sired this is probably the better way of doing it, although the chart can be used for the same purpose, using a larger scale than the miles on the chart. No matter how much practice he has had, the student can never, be- come too proficient in this bearing work. ANOTHER HANDY BEARING. It oftentimes occurs in thick weath- er that it clears up about the time you are abreast of a place and you want to know how far you are off the land. You. have gone too far. to get..a Dodge or 4-point bearing; here is a good method for this purpose: Note the time carefully when it bears ex- actly 261%4° (2% points) before the beam, and again when it has the same bearing abaft the beam. The distance run between bearings is the distance of the object when it was abeam. -- These bearings forming close upon an equilateral triangle (a _ triangle whose angles are 60°, consequently each sidé is equal) give a specially fa- vorable result. Ex--At 4 o'clock Harbor Beach light bore 261%4° -before the beam; at 4:19 it was abeam, and at 4:38 it bore 2614° abaft the beam. Ship steaming 13 miles an hour against a head wind that stops her progress two miles an hour. Required the distance from the light at 4:19 when it was abeam. The, ship ran 38 minutes between bearings so we get this statement: 60m. + 38m. +: 13 miles: x miles; and x equals 8.2 miles, disregarding the effects of the wind. For the wind we get this proportion: 60m. : 38m.::: 2 miles x 'miles, and x. equals 1.2 miles, which deducted from 8.2 miles leaves 7 miles, the distance that the ship was from the light when she had it abeam, or at 4:19. TO PROVE IT ON THE CHART. To prove this on the chart (if you have no chart of Lake Huron, take any chart and assume a position) take a distance of seven miles between the points of the dividers and measure off abreast of the light or place, as near as you can see by the eye alone, and with the parallel rulers trace the line; draw a line exactly at right angles to this that will pass through or touch the outer extremity of the first line drawn; this represents the course that the vessel is steering.. Next lay off with the parallel ruler, or protractor, an angle of 6314° (90°--26%°) from this line representing the course (to come forward of abeam) transfer this angle to the object to the line repre-