PAPER 12. 7. 1872. February 4th.-Find the times of High Water A.M. and P.M. at Lerwick. 8. 1874. December 9th, at 9h 6m A.M., apparent time at ship; in lat. 59° 35'; long. 63° W.; Sun's amplitude by compass E. 60° S. Required the error of compass; and supposing the variation to be 29° W., Required the deviation of the compass for that position of the ship's head. 9. 1874. December 9th, P.M. at ship; in lat. 38° 9′ N.; altitude Sun's upper limb 16° 30′ 20′′; eye 23 feet; time by chronometer 8d 17h 13m 598; which was slow for mean noon at Greenwich 34m 278 on October 6th, and on August 26th was slow 35 4" for mean noon at Greenwich; index error +4' 31". Required the longitude. 10. 1874. December 12th, at 8h 37m A.M., mean time at ship; in lat. 40° 49' S.; long. 150° 49′ W.; Sun's bearing by compass S. 95° 38′ E.; altitude Sun's lower limb 45° 6' 50"; eye 24 feet; index error + 44". Required the error of the compass; and supposing the variation to be 11° 15′ E., Required the deviation of the compass for that position of the ship's head. 11. 1874. December 10th, A.M. at ship; lat. by acc. 4° 20' S.; long. 20° W.; alt. Sun's lower limb S. of observer 70° 10′ 30′′; eye 23 feet; time by watch 11h 13m 40s; which had been found to be slow of apparent time at ship 22m 35; diff. long. made West after the error on apparent time at ship was determined was 17'; index error +1′7′′. Required the latitude by the reduction to the meridian. 12. 1874. December 16th.-Meridian altitude of the star Markab 59° 39' bearing S.; eye 23 feet; index error -1′20′′. Required the latitude. ADJUSTMENTS OF THE SEXTANT. 1st. To set the Index Glass perpendicular to the plane of the instrument Move the index to the middle of the arc, look in the index glass and see if the true and reflected arcs are in one line; if they are not, adjust by the screws at the back of the index glass. 2nd. To set the Horizon Glass perpendicular to the plane of the instrument Place the index at nothing, hold the instrument horizontally and observe if the true and reflected horizons are in one; if they are not, adjust by the upper screw at the back of the horizon glass. 3rd. To set the Horizon Glass parallel to the Index Glass when the index is at nothing Place the index at nothing, hold the instrument vertically, and observe if the true and reflected horizons are in one line; if not, adjust by the lower screw at the back of the horizon glass. To find the Index Error: Bring the true and reflected suns into exact contact on both sides of nothing; half the difference of the two readings will be the index error; to be added if the off reading is the greater, but subtracted if the on reading is the greater. Example to find the index error :-suppose Off reading......34' 00" On reading......30 00 Difference..... 4 00 Index Error, Half Difference + 2' 00" to add, because the off reading is the greater. To test the accuracy of the observations, add the readings together and divide the sum by 4, the result should be the same as the sun's semidiameter for the day on which the observations are taken. It will sometimes happen that both readings are on the arc, or both off; in either case half the sum will be the index error. 4th Adjustment. To set the Axis of the Telescope parallel to the plane of the instrument— Turn the eye-piece of the telescope till two of the wires are parallel to the plane of the instrument; then bring two heavenly objects, which are not less than 90° apart, in contact on the wire nearest the instrument, and see if they remain in contact when removed to the outer wire; if not, adjust by the screws in the collar. THE LOG LINE. The Log-Line, with the aid of the Log-Glass, ascertains the rate at which the ship moves through the water. The length of the knot in feet must bear the same proportion to the feet in a nautical mile that the seconds run by the glass do to the seconds in an hour. TO FIND THE LENGTH OF THE KNOT Annex a cipher to the seconds run by the glass and divide by 6; or Multiply the feet in a nautical mile by the seconds run by the glass, and divide by the seconds in an hour. 6080 feet in a Nautical or Geographical mile. 5280 feet in a Land or Statute mile. EXAMPLE. Find the length of a knot corresponding to a 30 second glass. 6080 feet in a nautical mile. Seconds in an hour 3600)182400(50 ft. 8 in. length of knot. 18000 2400 12 inches in a foot. 3600)28800(8 inches. 28800 Find the length of a knot corresponding to a 28 second glass. Answer-47 feet 3 inches, nearly. Find the length of a knot corresponding to a 20 second glass. To find the length of a knot by the short method- 50 feet, length of knot. If there is any remainder after dividing by 6, multiply it by 2, and the result will be inches. By the above method Find the length of a knot for a 28 second glass. Find the length of a knot for a 20 second glass. THE LEAD LINE. The Lead line has "nine marks and eleven deeps." At 2 fathoms the mark is Leather, with two ends. Leather, with three ends. White rag. Red rag. Leather, with a hole in it. 3 Deep-sea lead lines are marked in a similar manner as far as 20 fathoms; after which, a piece of cord with an additional knot for every 10 fathoms; and at every five fathoms, between the tens, a piece of leather. LLOYD'S INSTRUCTIONS TO COMMANDERS & MATES FOR THE STOWAGE OF MIXED CARGOES. (Prepared by HENRY C. CHAPMAN & Co., Agents for Lloyd's, Liverpool.) I.-Owners, Commanders, and Mates of Ships are considered in law in the same situation as Common Carriers; it is, therefore, necessary that all due precautions be taken to receive and stow Cargoes in good order, and deliver the same in like good order. The law holds the Shipowner liable for the safe custody of the Goods, when properly and legally received on board in good order, and for the "delivery" to parties producing the Bill of Lading. The Captain's blank Bill of Lading should be receipted by the Warehouse Keeper or person authorized to receive the contents. Goods are not unfrequently sent alongside in a damaged state, and letters of indemnity given to the Captain by the Shippers for signing in good order and condition; this is nothing more or loss than conniving at fraud. Fine Goods are also often damaged in the Ship's hold by Lumpers, if permitted to use Cotton Hooks in handling Bales. All Goods must be received on board according to the custom of the Port where the cargo is to be taken in; and the same custom will regulate the commencement of the responsibility of the Master and Owners. 2.-HEMP, FLAX, WOOL, and COTTON should be dunnaged 9 inches on the Floors, and to the upper part of the bilge, the wing bales of the second tier kept 6 inches off the side at the lower corner, and 2 inches at the sides. Sand or damp gravel Ballast to be covered with boards. Pumps to be frequently sounded and attended to. Sharp-bottomed Ships one-third less dunnage in floor and bilges. Avoid Horn Shavings as dunnage from Calcutta. 3.-All CORN, WHEAT, RICE, PEASE, BEANS, &c., when in bulk, to be stowed on a good high platform, or dunnage wood, if not less than 10 inches, and in the bilges 14 inches dunnage; the pumps and masts cased; to have strong bulkheads, good |