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TIME OF HIGH WATER AT POINTS ON THE ATLANTIC COAST.

The Eastern Standard Time of High Water (except for the Florida stations, which are in Central Standard time) at the following stations may be found approximately for each day by adding to or subtracting from the time of high water at Sandy Hook (The Horseshoe) the hours and minutes annexed.

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EXAMPLE.-To find the approximate time of high tide at Atlantic City, N. J., on any day, find first the time of high water at Sandy Hook under the desired date, and then add 19 minutes, as in the above table; the result is the time of high water required.

Vineyard Haven, Mass.

Add

3 59

Washington Navy Yard, D. C.

Add

0 24

Watch Hill, R. I....

Add

1 10

West Point Light, N. Y.

Add

3 24

Wilmington, N. C.

Add

2 39

Willets Point, N. Y

Add

3 36

Wood's Hole, Mass.
Yorktown, Va...

Add

0 53

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Number 1, white flag, six feet square, indicates clear or fair weather. Number 2, blue flag, six feet square, indicates rain or snow. Number 3, white and blue flag (parallel bars of white and blue), six feet square, indicates that local rains or showers will occur, and that the rainfall will not be general. Number 4, black triangular flag, four feet at the base and six feet in length, always refers to temperature; when placed above numbers 1, 2, or 3 it indicates warmer weather; when placed below numbers 1, 2, or 3 it indicates colder weather; when not displayed, the indications are that the temperature will remain stationary, or that there will be no decided change. Number 5, white flag, six feet square, with black square in center, indicates the approach of a sudden and decided fall in temperature, and is usually ordered at least twenty-four hours in advance of the cold wave. When number 5 is displayed, number 4 is always omitted.

A special storm flag, red with black square in center (not shown above), is prescribed for use in North and South Dakota, Minnesota (except at Lake stations), Iowa, Nebraska, and Wyoming, to indicate high winds, accompanied by snow, with temperature below freezing.

When displayed on poles, the signals should be arranged to read downward; when displayed from horizontal supports, a small streamer should be attached to indicate the point from which the signals are to be read.

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INTERPRETATION OF COMBINATION BLASTS.

One long, alone..
Fair weather, stationary
temperature.
Two long, alone.......... Rain or snow, stationary
temperature.

One long and short....... Fair weather, lower tem-
perature.
Two long and two short.. Rain or snow, higher
temperature.

One long and three short.. Fair weather, cold wave.
Three long and two short. Local rains, higher tem-
perature.

By repeating each combination a few times, with an interval of ten seconds between, possibilities of error in reading the forecasts will be avoided, such as may arise from variable winds, or failure to hear the warning signal.

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A Storm Signal.-A red flag (eight feet square) with black center (three feet square) indicate that the storm is expected to be of marked violence.

A Red Pennant (five feet hoist and twelve feet fly) displayed with the flags indicates easterly winds-that is, from northeast to south, inclusive, and that the storm center is approaching.

A White Pennant (five feet hoist and twelve feet fly) displayed with the flags indicates westerly winds that is, from north to southwest, inclusive, and that the storm center has passed.

When the Red Pennant is hoisted above the storm signal, winds are expected from the northeast quadrant; when below, from the southeast quadrant.

When the White Pennant is hoisted above the storm signal, winds are expected from the northwest quadrant; when below, from the southwest quadrant.

Night Signals.-By night a red light will indicate easterly winds; a white light above a red light will indicate westerly winds.

The Hurricane Signal consists of two red flags with black centers, displayed one above the other, and will be used to announce the expected approach of tropical hurricanes, and also of those extremely severe and dangerous storms which occasionally move across the Lakes and the northern Atlantic

coast.

The Information Signal consists of a red or white pennant, displayed alone. When displayed at stations on the Great Lakes, indicates that winds are expected which, in the opinion of the forecast official, may prove dangerous to smaller classes of vessels and tows, without reference to any stated velocity. When displayed at stations on the Atlantic, Pacific, and Gulf coasts, indicates that the local observer has received information from the central office of a storm covering a limited area, dangerous only for vessels about to sail to certain points. The signal serves as a notification to shipmasters that information will be given them upon application to the local observer.

WIND-BAROMETER TABLE.

(From the Weather Bureau, Washington, D. C.)

The following table presents, in form for ready reference, atmospheric signs which have been found to presage certain weather changes and conditions over the middle and upper Mississippi and lower Missouri valleys, the Great Lakes, the Ohio Valley, and the Middle Atlantic and New England States:

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Rain within 18 hours that will continue a day or two.

Rain, with high wind, followed within two days by clearing, colder.

Clearing and colder within 12 hours.

.Severe storm of wind and rain imminent. In win-
ter, snow and cold wave within 24 hours.
Severe northeast gales and heavy rain or snow,
followed, in winter, by cold wave.

29.80, or below, and rising rapidly. Going to w...Clearing and colder.

The character of the precipitation, whether rain or snow, is governed by the temperature.

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On November 18th, 1883, all the principal railroads of the United States adopted a standard of time. The United States was divided into four sections, each of 15 degrees longitude, equivalent to one hour of time. The first, or eastern section, uses the 75th meridian, and includes all territory lying between the Atlantic Coast and an irregular line drawn from Detroit to Charleston, S. C., its most southern point. The second, or central section, uses the 90th meridian, and includes the territory between the last-mentioned line and an irregular line from Bismarck, N. D., to the mouth of the Rio Grande. The third, or mountain section, uses the 105th meridian, and includes the territory between the last-mentioned line and nearly the western borders of Idaho, Utah and Arizona. The fourth, or Pacific section, uses the 120th meridian, and covers the rest of the territory to the Pacific Coast. Standard time within each of these sections is uniform, and the time in each section differs from that of the next by exactly one hour.

TO OBTAIN CORRECT LOCAL TIME.

Apply to standard time by adding or subtracting the correction in minutes given in the table.

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Jackson, Miss.

Jacksonville, Fla.

Janesville, Wis.

Eastern. Sub. 6
Central. Sub. 4
Central. Sub. 43
Eastern. Add 16
Eastern. Sub. 16
Central. Sub. 5
Central. Sub. 3
Eastern. Sub. 20
Central. Add 10
Central. Add 22
Central. Add 33
Eastern. Sub. 21
Central. Add 28
Central. Add 23
Mountain. Sub. 0
Central. Sub. 14
Central. Add 28
Central. Sub. 3
Central. Sub. 9
Central. Add 40

Duluth, Minn.

Erie, Pa...

Evansville, Ind.

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Ft. Gibson, Cherokee Nation.. Central.

Sub. 21

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Central. Sub. 11
Central. Add 19
Central. Sub. 2
Central. Sub. 19
Central. Add 15
Eastern. Sub. 7
Central. Sub. 21
Central. Add 12
Central.

Jefferson City, Mo..
Kansas City, Mo.
Keokuk, la...
Knoxville, Tenn.
La Crosse, Wis..
Lawrence, Kan.
Lexington, Ky.
Little Rock, Ark.
Louisville, Ky...
Lynchburg, Va..
Memphis, Tenn.
Milwaukee, Wis..
Mobile, Ala....
Montgomery, Ala.
Nashville, Tenn..
New Haven, Conn..
New Orleans, La..
New York, N. Y.
Norfolk, Va..
Ogdensburg, N. Y
Omaha City, Neb.
Pensacola, Fla..
Philadelphia, Pa.
Pittsburg, Pa..
Portland, Me..
Providence, R. I.
Quincy, Ill.
Raleigh, N. C..
Richmond, Va..

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Add 16

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Time Difference Between the City of New York and the Principal Foreign Cities.

Antwerp..
Berlin

Bremen.
Brussels.

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Rome...

5 45,8

|

Hong Kong..

11 27.4

St. Petersburg..

9 24.8

Buenos Ayres.. Calcutta.

1 2.4 Liverpool. 11 49.2 London.

4 43.6

Valparaiso.....

0 9.3

4 55.9

Vienna.........

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Constantinople.. 6 51.9 | Madrid....

4 41.1 Halifax.........

6 1.2 0 41.5 Yokohama....... 9 45.5

0 22.2

TRUE TIME.

Divisions of Time.

There are two kinds of time - Clock or meantime, and apparent or sun-time. Clock-time is always right, while sun-time varies every day, the sun very seldom being on the meridian at 12 o'clock. A Solar day differs in length owing to the ellipticity of the earth's orbit, etc.; but a mean Solar day, as recorded by clock-time, is twenty-four hours long.

An Astronomical day begins at noon and is counted from the first to the twenty-fourth hour.

A Civil day commences at midnight and is counted from the first to the twelfth hour.

A Nautical day is counted as a Civil day, but commences like an Astronomical day, at noon. A Calendar month varies from twenty-eight to thirty-one days.

A mean Lunar month is twenty-nine days, twelve hours, forty-four minutes, two seconds and a small fraction.

A Solar year, r the transition from one vernal equinox to another, consists of 365.24244 Solar days, or 365 days, five hours, forty-eight minutes and 49.536 seconds.

A Julian year is 365 days: a Gregorian year is 385.2425 days. Every fourth year, or leap year, has 366 days.

TWILIGHT.

Twilight is the faint light which precedes sunrise and follows sunset for some hours before the actual appearance and disappearance of the sun. It is caused by the reflection of the sun's rays from the upper strata of the atmosphere, and disappears when the sun is about 18° below the horizon. From this circumstance, and from a knowledge of the diameter of the earth, the height of the atmosphere can be computed, and has been thus found to be between 45 and 50 miles. It is probable, however, that it extends much farther, but if so, it must be of such extreme tenuity that it is incapable of reflecting the sun's rays.

LENGTH OF SEASONS.

Spring lasts from March 21 to June 21, or 92 days; summer from June 21 to September 21, or 92 days; autumn from September 21 to December 21, or 91 days, and winter from December 21 to March 21, or 90 days, or 91 days in the case of leap year, that is, the interval from the autumnal to the vernal equínox is about three days shorter (neglecting the odd hours and minutes) than the interval from the vernal to the autumnal equinox. This discrepancy is due to the form of the earth's orbit, the earth describing during the autumn and winter months that portion of its orbit nearest the sun, and therefore with the greatest velocity. We are nearest to the sun about the 1st of January and farthest about the 1st of July.

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