Nautical Almanac

“ His special field has been that of "exact" astronomy—the prediction of the motions of the heavenly bodies from their mutual gravitation—the perfection of the tables and other data, from which the "Nautical Almanac" is prepared, in order that the navigator and surveyor may be enabled to find their positions by sea or land. When the late Admiral Davis founded the "American Nautical Almanac," some twenty-five years ago, the tables and other materials for its construction were extremely imperfect, but Prof. Newcomb's studies have all tended to their improvement. ”

“ In the Nautical Almanac, the permanent table for increments also includes corrections for v, the difference between the actual change of GHA in one hour and a constant value used in the interpolation tables; and d, the change in declination in one hour.
In the Nautical Almanac, v is always positive unless a negative sign (−) is shown. This occurs only in the case of Venus. For the Sun, the tabulated values of GHA have been adjusted to reduce to a minimum the error caused by treating v as negligible; there is no v tabulated for the Sun. ”

“ But the most important change that had come to the sea service was in the methods of finding a ship's position at sea. Hadley's sextant was in use in 1731, Harrison's chronometer in 1762, and five years later the first number of the Nautical Almanac was published, so that when Cook sailed longitude was no longer found by rule of thumb, and the great navigator, more than any other man, was able to and did, prove the value of these discoveries. ”

“ Ultimately, however, the accuracy of the watch, and its indispensableness in the perfected form of the chronometer, having been fully demonstrated, the method of lunars became practically obsolete and the mariner was able to determine his longitude with the aid of sextant, chronometer, and Nautical Almanac, by means of direct observation of the altitude of the sun by day and of sundry fixed stars by night, a much simpler calculation sufficing than was required by the older method. ”

“ For the use of men engaged in practical astronomy, it is very convenient to consider the sun,27 moon, stars, and planets as going round the earth at rest. For instance, seamen use the heavenly bodies as in a way hands of a huge clock from which they can know the time and their position on the earth. “The Nautical Almanac,” which is printed yearly, gives the true position of these heavenly bodies for every hour, minute, and second of the year, and I will presently show how useful this is to sailors. ”

“ In the Nautical Almanacs, which are constructed for several years in advance, the situations and nearly everything connected with the different planets are calculated for every day in the year, and can be found, if required, for any minute in any day you please, for 10,000 years to come. ”

“ From data furnished from the Royal Observatory, is compiled an extraordinary prophetic Almanack from which all other almanacks are copied. It foretells to a second when and where each of the planets may be seen in the heavens at any minute for the next three years. The current number of the Nautical Almanack is for the Year of Grace 1853.
In this quiet sanctuary, then, the winds are made to register their own course and force, and the rain to gauge its own quantity as it falls; the planets are watched to help the mariner to steer more safely over the seas ”

“ At 3 a.m. 9th October, barometer 28.21, took in main top-sail, and put ship on starboard tack, being in the right hand semicircle; at 4.30 the scene was fearful; gust upon gust, and sea running high but not breaking owing to the wind. At 6 a.m. barometer 27.50, men lashed on deck, nothing visible of ship but a portion of her weather deck, on her beam-ends, yard-arms in the water. At 7 a.m. barometer 27.29, when suddenly it lulled and the centre passed. Drift, up to this time, 51/2 knots per hour, N.W., was expecting every moment to hear the ship crushing on the reefs. ”

“ Time depends upon the sun, and when the ship is going east she goes to meet the sun; and it becomes noon, that is, midday, earlier. When the ship is going west, she goes away from the sun, and then it becomes noon later. Thus noon has to be fixed every day anew, and a clock going regularly all the time would be continually getting wrong. Then, besides the rolling and pitching of the ship would derange the motion of the weights and pendulum of the clock. ”

“ Every ship carries a marine chronometer, which is a time-keeper of the most careful construction, whose accuracy has been tested with the utmost precision—which is plainly a matter of the utmost importance to a vessel when it is remembered that an error of four seconds of time represents about one and one-tenth statute miles, enough to wreck a ship on a lee shore when the captain, following the chronometer, supposed himself at a safe distance from the shoal or shore. ”

“ They therefore determined to extend the indulgence, and take the consequence, whether to live or die. On the 8th of February, another of the crew died. From this time to the 17th, their sufferings were extreme. At seven o'clock, A.M. of that day, they were aroused from a lethargy by the cheering cry of the steersman, "there's a sail!" The boat was soon descried by the vessel, the brig Indian, Captain Grozier, of London, which took them on board, latitude 33° 45' S., longitude 81° 3' W. They were treated by Captain Grozier with all the care and tenderness which their weak condition required. ”

“ Weighing at 1 p.m.., we lay along shore until arriving at the above point, to which I gave a wide berth, as a heavy sea was breaking over a long shoal which ran from it, and the wind was freshening from the N.W., whence it soon blew a gale, and brought us under close-reefed topsails. A strong weather tide rose so short and high a sea, that for throe hours the ship was unmanageable, and pitched bowsprit under every moment. We now found, that although with our head off this truly dangerous shore, we were nearing it rapidly, and driving bodily down on the shoal. ”

“ As the early morning passed and 8 o’clock drew nigh, the idle seamen in the lookout boat suddenly bent to their oars and drove the swift cutter, with signals fluttering in the air, into the bay. The long roll of the drums beating to quarters on the Yankee ships followed. ”

“ The great September waves breaking at the base of the Neversink Highlands, far in advance of the swiftest pilot-boat, carry tidings. And full often, they know the last secret of many a stout ship, never heard of from the day she left port. Every wave in my eyes seems a soul. ”

“ At eight o’clock, the weather appearing suspicious, and the wind beginning to blow, the top-gallant-masts were got down on deck: at half-past it came on squally, and we veered away to a cable and a half. At nine the ship was found to be driving, and in only eleven fathoms water; the small bower was instantly let go, which brought her up in ten fathoms, The lower-yards and top-masts were now struck, as close down as they could be got. The moon was not visible, but we had sufficient light to shew us our dangerous situation ”

“ That is to say, if I were sailing west, in the night-time, and my position, according to my dead reckoning from my afternoon chronometer sight, was shown to be seven miles off the land, why, at that very moment I would be crashing on the reef. Next I compared my chronometer with Captain Wooley's. Captain Wooley, the harbourmaster, gives the time to Suva, firing a gun signal at twelve, noon, three times a week. According to his chronometer mine was fifty-nine seconds fast, which is to say, that, sailing west, I should be crashing on the reef when I thought I was fifteen miles off from it. ”

“ By eleven o’clock the wind veered to the southwest and became squally, the tide began to flow and the swell to heave. At 11.30 the ship began to move, but just then the hawser parted. Captain Arthur immediately ordered the boats to pull away about forty-five degrees abaft the starboard beam; the breeze freshened and gave a greater impulse to the strain of the stream cable, and, to our delight, the ship launched off and got sternway, which, the boats assisting, swung her around on her heel with her head to the northward. ”

“ For these and other reasons, a ship's captain places little reliance on what is called "the day's work"—that is, the change in the ship's position from noon to noon as estimated from the compass-courses entered in the log-book, and the distances supposed to be run on these courses. It is absolutely essential that such estimates should be carefully made, because, under favorable conditions of weather, there may be no other means of guessing at the ship's position. But the only really reliable way of determining a ship's place is by astronomical observations. ”

“ This happened in ancient Greece, where the stars served for the time-reckoning of sailors and peasants while the lunisolar calendar was developed and extended under sacral influence; the festival calendar, which was regulated and recorded by the moon, became the official civil calendar. It was only later that the stellar calendar was systematically brought under the influence of the fully developed astronomy and of the Julian calendar.
In sailing, the stars afford to the primitive sea-faring peoples the only means of finding their way when the land can no longer be seen. ”

“ As you can readily imagine, the life of a ship’s crew, ice-bound, during the long, dark, northern winter is not an enviable one. Suffice it to say that we got through it with probably less than the ordinary amount of hardship, and were very glad to catch a glimpse of the sun about the beginning of April, as it looked like a sign of release, though the captain did not think the ice would break up for at least six weeks longer. ”

“ Part of the preparation was to let the captain know beforehand that it was eight o'clock, and get his authority that it might be so; subject always to the yet higher authority that the yards and sails were ready. If they were not, so much the worse for eight o'clock. It had to wait quite as imperatively as the sun did for Joshua. Sunset, when the masts and yards came down, was equally under bonds; it awaited the pleasure of the captain or admiral. Indeed, in my time a story ran of a court-martial at a much earlier day, sitting in a capital case. By law, each day's session must end by sundown. ”

“ The day passed without any incident of vital importance. It is true they sighted the smoke of a steamer hull down on the southern horizon, but they saw nothing else across the waste of heaving water. Every now and again the captain woke up and made a few remarks on the nature of authority, and what he proposed doing to those who did not "knuckle under." But the night fell without any signs of mutiny on the part of the scientific crew.
In the very early dawn the astronomer, who had slept in uneasy snatches, woke up for the tenth time and changed his position. ”

“ Immense schools of porpoises passed to-day, and Sherman struck and secured one of the largest we have seen. Many of the men have employed themselves in preparing the skin for belts. A whale passed us in the afternoon, coming close along-side the bark. And to keep up the excitement, a sail was discovered on our starboard bow, the only one we have seen for fifty-three days.
September 6. We were aroused this morning at four o'clock by the startling cry of "breakers." Our ship instantly became a scene of confusion, and the passengers rushed on deck from every quarter. ”

“ Even in the matter of speed, the sailing ship more than held its own for a generation or so after the steamship had been placed in commission. In 1851 the American clipper Flying Cloud made 427 knots in twenty-four hours; and The Sovereign of the Seas bettered this by averaging over eighteen miles an hour for twenty-four consecutive hours. The Atlantic record for sailing vessels is usually said to have been made in 1862 by the clipper ship Dreadnought in a passage between Queenstown and New York, the time of which is stated as nine days and seventeen hours. ”

“ Though the 1st of August commenced with a heavy gale from E.N.E. and very foggy weather, we proceeded to the reef, after much fatigue in dragging the boats over the flats, supposing that our best choice of getting forward would be bypassing on the outside of it. But there finding heavy ice lying aground, and so closely packed as to preclude the possibility of putting the boats into the water, it was determined to examine the channel by walking along the edge of the reef. ”

“ By an observation we found ourselves in the latitude of 30 degrees 2 minutes south. Twelve of our crew were dead by immoderate labor, and ill food, the rest were in a very weak condition. On the fifth of November, which was the beginning of summer in those parts, the weather being very hazy, the seamen spied a rock, within half a cable's length of the ship; but the wind was so strong that we were driven directly upon it, and immediately split. Six of the crew, of whom I was one, having let down the boat into the sea, made a shift to get clear of the ship and the rock. ”

“ To steady her, the storm-stay-sails were again set, which had scarcely been effected, when a heavy sea made a clean sweep of everything moveable on her upper deck, tore a boat away from the larboard quarter, and ripped up the weather boards of the quarter deck. The whole of the ship’s company were now busily employed in pumping and bailing, as leaks had been sprung in every direction, and the waves were making a fair breach over her. ”