EXERCISES ON THE CHART. FOR ONLY AND FIRST MATES. NORTH SEA. (1) Latitude 55° 28' N. Longitude 0° 30' W. Required the Compass Course and Distance to Tynemouth. (2) Latitude 52° 15' N. Longitude 2° 15' E. Required the Compass Course and Distance to Lowestoft. (3) Latitude 53° 35' N. Longitude 0° 55' E. Required the Compass Course and Distance to the Dudgeon. (4) Latitude 55° 5' N. Longitude 0° 5' E. Required the Compass Course and Distance to Hartlepool. ENGLISH CHANNEL. (1) Latitude 50° 30' N. Longitude 0° 55' E. Required the Compass Course and Distance to Dungeness. (2) Latitude 50° 10' N. Longitude 3° 10' W. Required the Compass Course and Distance to Portland. (3) Latitude 48° 5' N. Longitude 6° 30' W. Required the Compass Course and Distance to Ushant. (4) Latitude 48° 55' N. Longitude 6° 5' W. Required the Compass Course and Distance to the Lizard. BRISTOL CHANNEL AND SOUTH COAST OF IRELAND. (1) Latitude 50° 50' N. Longitude 10° 35' W. Required the Compass Course and Distance to Fastnet Rock. (2) Latitude 50° 45' N. Longitude 6° 20' W. Required the Compass Course and Distance to the Longships. (3) Latitude 51° 10' N. Longitude 6° 10' W. Required the Compass Course & Distance to Lundy Island light. (4) Latitude 50° 55' N. Longitude 6° 55' W. Required the Compass Course and Distance to Trevose Head. ORDINARY MASTER. ENGLISH AND BRISTOL CHANNELS, AND SOUTH COAST OF IRELAND. (1) Lizard Light bearing E. 1 S. by Compass. Longships Light bearing N. I W. by Compass. Required the Compass Course and Distance to the Seven Stones Light, and Latitude and Longitude of the Ship. (2) Caldy Island Light bearing E.N.E. by Compass. Lundy Island Light bearing S. by E. E. by Compass. Required the Compass Course and Distance to the Smalls Light. (3) Fastnet Light bearing N.E. } E. by Compass. Skelligs bearing N. W. by Compass. Required the Compass Course and Distance to the Old Head of Kinsale; also the Latitude and Longitude of the Ship. NORTH SEA. (1) Sunderland Light bearing S.W. by Compass. Coquet Island bearing N. W. 1 W. by Compass. Required the Compass Course and Distance to Hartlepool. (2) Kentish Knock Light bearing S.W. by S. by Compass. Galloper Light bearing S.E.S. by Compass. Required the Compass Course and Distance to Shipwash Light. (3) Dudgeon Light bearing W. N. by Compass. Hasbro' Sand-end Lights bearing S.S.W. & W. by Compass. Cromer Light bearing S. by E.; The Outer Dowsing Light bearing E.S.E. Find the Ship's place, and the Course and distance to Flambro' head. (5) Bell Rock Light bearing N. by W.; May Island Light bearing W.S.W. Find the Ship’s Latitude and Longitude, and the Course and Distance to the Longstone Light. (6) Hartlepool Heugh Light bearing W.N.W.; Huntcliff bearing S.W. by S. Find the Ship's place, and the Course and Distance to Tyne mouth Light. (7) The Shipwash Light bearing W. by N.; The Galloper Light bearing S.S.W. Find the Ship's place and the Course and Distance to the Corton Light Vessel. QUESTIONS ON SHAPING A COURSE IN A TIDE-WAY. (1) A Ship sailing 7 miles an hour by log, in a current on her port beam, whose drift is 6 miles in 4 hours. What Course must she steer to fetch Tynemouth Light, the direct Course to which is N. W. by W., distant 30 miles. (2) A Ship in lat. 54° 30' N., long. 0° 37' E., is bound to Hartlepool; the tide is setting N.E. by N., with a drift of 3 miles in 2 hours, and the Ship’s rate by the log is 10 miles per hour. Find the Course to be steered to reach her port. (3) A Ship sails by log 9 miles per hour, in a current 2 points abaft her starboard beam, drift 3 miles per hour. Required her Course to Sunderland when Tynemouth Light bore N.W. by W., and Whitby Lights bore S.W. PROBLEM, TO FIND THE SHIP'S DISTANCE FROM A POINT OF LAND, OR A LIGHT, WITHOUT A TABLE, This Problem is of great service when sailing up or down Channel, or along any coast, and is as follows: Suppose Beachy Head bears two or three points on the port bow, then let the Ship keep on her course till it bears the same number of points to the left of the first bearing ; the distance the Ship has run in the interval is her distance from the light at the time of taking the second bearing. Let A be a Ship steering East; B a Light bearing three points on the port bow, that is, N.E. by E. ; she proceeds on her course till the Light bears three points to the left of N.E. by E., that is, N.N.E. ; then C B is equal to C A, by 6th Proposition, 1st Book of Euclid. Communicated by J. Newton, F.R.A.S., Well Street Navigation Schools, London. NORTH SEA. (1) Sunderland Light bearing S.W. by Compass. Coquet Island bearing N.W. 1 W. by Compass. Required the Compass Course and Distance to Hartlepool. (2) Kentish Knock Light bearing S.W. by S. by Zompass. Galloper Light bearing S.E.S. by Compass. Required the Compass Course and Distance to Shipwash Light. (3) Dudgeon Light bearing W. } N. by Compass. Hasbro' Sand-end Lights bearing S.S.W. & W. by Compass. Required the Latitude and Longitude of the Ship. (4) Cromer Light bearing S. by E.; The Outer Dowsing Light bearing E.S.E. Find the Ship's place, and the Course and distance to Flambro' Head. (5) Bell Rock Light bearing N. by W.; May Island Light bearing W.S.W. Find the Ship's Latitude and Longitude, and the Course and Distance to the Longstone Light. (6) Hartlepool Heugh Light bearing W.N.W.; Huntcliff bearing S.W. by S. Find the Ship's place, and the Course and Distance to Tyne mouth Light. (7) The Shipwash Light bearing W. by N.; The Galloper Light bearing S.S.W. Find the Ship’s place and the Course and Distance to the Corton Light Vessel. QUESTIONS ON SHAPING A COURSE IN A TIDE-WAY. (1) A Ship sailing 7 miles an hour by log, in a current on her port beam, whose drift is 6 miles in 4 hours. What Course must she steer to fetch Tynemouth Light, the direct Course to which is N. W. by W., distant 30 miles. (2) A Ship in lat. 54° 30' N., long. 0° 37' E., is bound to Hartlepool; the tide is setting N.E. by N., with a drift of 3 miles in 2 hours, and the Ship’s rate by the log is 10 miles per hour. Find the Course to be steered to reach her port. (3) A Ship sails by log 9 miles per hour, in a current 2 points abaft ħer starboard beam, drift 3 miles per hour. Required her Course to Sunderland when Tynemouth Light bore N.W. by W., and Whitby Lights bore S.W. PROBLEM, TO FIND THE SHIP'S DISTANCE FROM A POINT OF LAND, OR A LIGHT, WITHOUT A TABLE, This Problem is of great service when sailing up or down Channel, or along any coast, and is as follows : Suppose Beachy Head bears two or three points on the port bow, then let the Ship keep on her course till it bears the same number of points to the left of the first bearing ; the distance the Ship has run in the interval is her distance from the light at the time of taking the second bearing. Let A be a Ship steering East; B a Light bearing three points on the port bow, that is, N.E. by E. ; she proceeds on her course till the Light bears three points to the left of N.E. by E., that is, N.N.E.; then C B is equal to C A, by 6th Proposition, 1st Book of Euclid. ܙ• Communicated by J. Neuton, F.R.A.S., Well Street Navigation Schools, London. |