movement the contrary; as likewise a steady barometer, which, when continued, and with dryness, foretells very fine weather. 40. A rapid and considerable fall is a sign of stormy weather, with thunder and lightning, and rain, hail, or snow. Alternate rising and sinking indicates unsettled and threatening weather. 41. The greatest depressions of the barometer are with gales from south-east, south, or south-west; the greatest elevations, with wind from north-west, north, or north-east, or with calm. 42. Though the barometer generally falls with a southerly, and rises with a northerly wind, the contrary sometimes occurs; in which cases the southerly wind is usually dry with fine weather, or the northerly wind is violent and accompanied by rain, snow, or hail; perhaps with lightning. 43. When the barometer sinks considerably, much wind, rain (perhaps hail), or snow will follow, with or without lightning.* The wind will be from the northward, if the thermometer is low (for the season); from the southward if the thermometer is high. Occasionally a low glass is followed or attended by lightning only, while a storm is beyond the horizon. 44. A sudden fall of the barometer, with a westerly wind, is sometimes followed by a violent storm from north-west, or north, or north-east. 45. If a gale sets in from the east or south-east, and the wind veers by the south, the barometer will continue falling until the wind is near a marked change, when a lull may occur; after which the gale will soon be renewed, perhaps suddenly and violently, and the veering of the wind toward the north-west, north, or north-east, will be indicated by a rising of the barometer with a fall of the thermometer. 46. Three causes (at least)† appear to affect a barometer. 47. I. The direction of the wind, the north-east wind tending to raise it most, the south-west to lower it the most, and winds from points of the compass between them, proportionally, as they are nearer one or the other extreme point. 48. North-east and south-west may appropriately be called the wind poles (as Dové showed). 49. The range, or difference of height shown, due to change of direction only, from one of these bearing to the other (supposing force and * "When the glass falls low prepare for a blow; + Electrical effects are yet uncertain. moisture to remain the same) amounts in the latitudes of Great Britain to about half an inch (as read off). 50. II. The quantity, taken by itself, of vapor, moisture, rain, or snow, in the wind, or current of air (direction and strength remaining the same), seems to cause a change, amounting in an extreme case to about half an inch. 51. III. The force alone of wind from any quarter (moisture and direction being unchanged) is preceded, or foretold, by a fall or rise, according as the strength will be greater or less, ranging in an extreme. case to more than two inches. 52. Hence, supposing the three causes to act together, in extreme cases, the height would vary from near thirty-one inches (30.9) to about twenty-seven (27.0) inches, which has happened, though rarely (and even in tropical latitudes). 53. In general, the three causes act much less strongly, and are less in accord, so that ordinary varieties of weather occur much more frequently than extreme changes. 54. It is not by any means intended to discourage attention to what is called "weather wisdom." On the contrary, every prudent person will combine actual observation of the elements with such indications as he may obtain from instruments, and will find that the more accurately the two sources of foreknowledge are compared and combined, the more satisfactory their results will prove. 55. A barometer begins to rise considerably before the conclusion of a gale, sometimes even at its commencement. Although it falls lowest before very high winds, it frequently sinks much before heavy rain. The barometer falls, but not always, on the approach of thunder and lightning.* Before and during the earlier part of settled weather it usually stands high, and is stationary; the air being dry and comparatively quiet. 56. Instances of fine weather, with a low barometer, occur, however, rarely, but they are always preludes to a duration of wind or rain, if not both, or they indicate bad weather in the vicinity. 57. After very warm and calm weather, a storm, or squall, with rain, may follow, as likewise locally at any time when the atmosphere is heated much above the usual temperature of the season. 58. Allowance should invariably be made for the previous state of the *Thunder clouds rising from northeastward, against, or above the lower wind, do not usually cause a fall of the barometer. barometer during some days, as well as some hours, because its indications may be affected by distant causes, or by changes close at hand. Some of these changes may occur at a greater or less distance, influencing neighboring regions, but not visible to each observer whose barometer feels their effect. 59. There may be heavy rains or violent winds beyond the horizon and the view of an observer, by which his instruments may be affected considerably, though no particular change of weather occurs in his immediate locality. 60. It may be repeated, that the longer a change of wind or weather is foretold before it takes place, the longer the presaged weather will last; and, conversely, the shorter the warning, the less time whatever causes the warning, whether wind, or a fall of rain, or snow, will continue. 61. Sometimes severe weather from the southward, not lasting long, may cause no great fall, because followed by a duration of wind from the northward; and at times the barometer may fall with northerly winds and fine weather, apparently against these rules, because a continuance of southerly wind is about to follow. By such changes as these one may be misled, and calamity may be the consequence, if not duly forewarned. NOTE. A few of the more marked signs of weather, useful to seamen, are the following: * Whether clear or cloudy, a rosy sky at sunset presages fine weather; a sickly greenish hue, wind and rain; tawny, or coppery clouds, wind; a dark (or Indian) red, rain; a red sky in the morning, bad weather, or much wind, perhaps also rain; a gray sky in the morning, fine weather; a high dawn, wind; a low dawn, fair weather.+ Soft-looking or delicate clouds foretell fine weather, with moderate or light breezes; hard-edged oily-looking clouds, wind. A dark, gloomy, blue sky is windy; but a light, bright blue sky indicates fine weather. Generally, the softer clouds look, the less wind (but perhaps more rain) may be * "When the sun sets in a clear, an easterly wind you need not fear." A high dawn" is when the first indications of daylight are seen above a bank of clouds. A "low dawn" is when the day breaks on or near the horizon, the first streaks of light being very low down. expected; and the harder, more "greasy," rolled, tufted, or ragged, the stronger the coming wind will prove. Also, a bright yellow sky at sunset presages wind; a pale yellow, wet; orange or copper-colored, wind and rain; and thus, by the prevalence of red, yellow, green, gray, or other tints, the coming weather may be foretold very nearly-indeed, if aided by instruments, almost exactly. Light, delicate, quiet tints or colors, with soft, indefinite forms of clouds, indicate and accompany fine weather; but gaudy or unusual hues, with hard, definitely outlined clouds, foretell rain, and probably strong wind. Small inky-looking clouds foretell rain; light scud clouds driving across heavy masses show wind and rain, but, if alone, may indicate wind only, proportionate to their motion. High upper clouds crossing the sun, moon, or stars, in a direction different from that of the lower clouds, or the wind then felt below, foretell a change of wind toward their direction.* After fine clear weather, the first signs in the sky of a coming change are usually light streaks, curls, wisps, or mottled patches of white distant cloud, which increase, and are followed by an overcasting of murky vapor that grows into cloudiness. This appearance, more or less oily, or watery, as wind or rain will prevail, is an infallible sign. Usually the higher and more distant such clouds seem to be, the more gradual, but general, the coming change of weather will prove. Misty clouds forming or hanging on heights, show wind and rain coming, if they remain, increase, or descend. If they rise, or disperse, the weather will improve, or become fine. When sea birds fly out early, and far to seaward, moderate wind and fair weather may be expected; when they hang about the land, or over it, sometimes flying inland, strong winds with stormy weather are probable. As, besides birds, many creatures are affected by the approach of rain or wind, their indications should not be slighted by an observer who wishes to foresee changes. There are other signs of coming change in the weather known less generally than is desirable, and, therefore, worth notice, such as when birds of long flight fly up and down, or low, rain or wind may be expected; *In the tropics, or regions of trade winds, there is generally an upper and counter current of air, with very light clouds, which is not an indication of any approaching change. In middle latitude such upper currents are not so frequent (or evident!) except before a change of weather. also, when smoke from chimneys does not ascend readily (straight upwards during calm), unfavorable change is probable. Dew is an indication of coming fine weather; so is fog. Neither of these two formations begins under an overcast sky, or when there is much wind. One occasionally sees fog rolled away, as it were, by wind, but seldom or never formed while it is blowing with any considerable force, though it exists with wind. HOW TO KEEP THE LOG-BOOK. The log-book is a journal of what transpires on board ship. Over the first column is marked the letter H, standing for the hours of the day and night, the figures below it running consecutively from midnight to noon (1 to 12), and then from noon to midnight (1 to 12), making the same divisions of the 24 hours as are used on shore. (The log-book is kept in civil time now, instead of the old method of sea time.) Over the next column will be found the letter "K," standing for miles, or, as they are called nautically, "knots." Adjoining will be seen the letter "F," meaning furlongs; and here I desire to explain that a furlong of distance recorded in a log-book means one-eighth of a knot, or mile. Suppose the ship had sailed by the patent log 10 miles and a half, it would be entered in the log-book as 10 knots and 4 furlongs. When the courses and distances are footed for the various courses, the furlongs are added and divided by 8, and the answer carried to the column of knots. Following along to the right we next find the word "Courses," under which heading, and against the hour, will be noted the course of the ship by the compass on board. Every time the ship's course is changed it must be recorded in the log-book. If the course is altered between the hours, then draw a line across the page between the rulings to allow for the length of time the ship was on such course over the hour, distance made, course sailed, direction of wind, etc. We next come to the column of "Leeway." Leeway." In this column will be jotted down the amount of leeway the ship makes, determined by the officer of the watch. The next two columns are for the standing of the thermometer and barometer. The last column is headed "Remarks," and under this head will be |