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1907

Month.

MEAN TIME OF TRANSIT (AT WASHINGTON) AND POLAR DISTANCE OF POLARIS.

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H. M. S. 10 49 8 10 9 54

9 30 41

O
1 11 31
1 11 34
1 11 36

P. M.

H. M. S.
8 47 35
88 25
7 29 15

O III 1 11 38

1 11 39

1 11 40

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From June 16 to August 1 both the upper and lower transits take place during daylight. The azimuth at the time of greatest eastern or western elongation can be easily computed from the formula:

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where A denotes the azimuth, p the polar distance, and 7 the latitude of the place.

DATE OF GREATEST ELONGATION.

To find the time of greatest eastern or western elongation, let Idenote the hour angle, and l and p as before, then we shall have

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This quantity, H, added to or subtracted from the time of transit given above, according to the elongation required, will give the mean time of the greatest elongation at any place whose north latitude is l.

Star Table.

FOR IDENTIFYING THE PRINCIPAL FIXED STARS.

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8 Persei (Algol)...
aTauri (Aldebaran).
"Auriga (Capella).
BOrionis (Rigel).
aOrionis (Betelguese).
aCanis Majoris (Sirius).
aGeminorum (Castor) N 32 76 5.7 +18 3.7 a Aquarii
BGeminorum (Pollux).. N 28 16+6 16.6 +18 14.6 a Piscis Aus.
aCanis Minor.....

8 193 47.6 +15 45.6 aAquila (Altair).
N 7 23+ 4 27.6 +16 25. 6 aCygni (Deneb)
S 16 35+5 18.4 +17 16.4 aCephei

N 5 29 +6 11.6 +18 9.6 a Pegasi (Markab).

Declination

On Meridian.
Upper. Lower.

O I
H. M. H. M.
N 12 28+ 8 40.1 +20 38, 1
S 10 3711 56.5 +23 54, 5
N 19 43 +12 47.5 +0 45.5
N 74 35+13 27.5+1 25, 5
N 27 4 +13 49.71 47.7
S 26 12 14 59. 3 2 57.3
N 8 4117 9.35 7.3
N 8 36 +18 21.4 +6 19.4
N 44 55+19 13.5 +7 11. 5
N 62 9 +19 51.57 49.5
S 0 49 +20 35.8 +8 33.8
S 30 10 +21 27.1 + 9 25. 1
N 14 39 +21 34.7 +9 32.7

To find the time of the star's transit add or subtract, according to the sign, the numbers in the second column of figures to the date of the transit of the pole star given above. Thus, for a Andromeda February 1. Lower Transit of Polar Star is 4 h. 43 m. 36 s. A. M, to which add 10 h. 40 m. and we have 3 h, 23 m. 36 s. P. M.; for December 1, we find 7 h. 29. 38s. P. M., etc.

STAR TABLE-Continued.

APPROXIMATE PARALLAX AND DISTANCE IN LIGHT-YEARS OF SOME OF THE PRINCIPAL FIXED STARS.

By light-years is to be understood the number of years light requires to travel from the star to us.

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The determination of stellar parallax is one of the most difficult and refined problems in practic.l or observational astronomy. It is to find the angle which the semi-diameter of the earth's orbit subtends at the star-an angle always very small as seen from the above table and which cannot be measured directly but by various processes too complicated to be explained here.

Thermometers.

COMPARATIVE SCALES.

Reau- Centi- Fahr

100. 212. WATER BOILS

Rules for Foretelling the Weather.

ADAPTED FOR USE WITH ANEROID BAROMETERS.

A RISING BAROMETER.

A RAPID rise indicates unsettled weather.

A gradual rise indicates settled weather.

A rise with dry air and cold increasing in Summer indicates
AT SEA-Wind from the northward; and if rain has fallen, better weather
LEVEL.
may be expected.

mur,

grade, enheit,

80.

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A rise with moist air and a low temperature indicates wind and rain from the northward.

A rise with southerly winds indicates fine weather.

A STEADY BAROMETER.

With dry air and seasonable temperature indicates a continuance of very fine weather.

A FALLING BAROMETER.

A rapid fall indicates stormy weather.

A rapid fall with westerly wind indicates stormy weather from the northward.

A fall with a northerly wind indicates storm, with rain and hail in Summer, and snow in Winter.

A fall with increased moisture in the air, and heat increasing, indicates wind and rain from the southward.

A fall with dry air and cold increasing in Winter indicates snow. A fall after very calm and warm weather indicates rain with squally weather.

The barometer rises for northerly winds, including from northwest by north to the eastward for dry, or less wet weather, for less wind, or for more than one of these changes, except on a few occasions, when rain, hail, or snow comes from the northward with strong wind.

The barometer falls for southerly wind, including from southeast by south to the westward, for wet weather, for stronger wind or for more than one of these changes, except on a few occasions, when moderate wind, with rain or snow, comes from the northward.

The above printed rules are in use by the Seawanhaka-Corinthian Yacht Club of New York.

CRITICAL WINDS.

DURATION OF DIFFERENT KINDS OF WEATHER IN THE SEVERAL
STORMS-VICINITY OF NEW YORK.
Clear Cloudy Rain Clearing
Hours. Hours. Hours.

Hours.

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OBJECTS VISIBLE AT SEA-LEVEL IN CLEAR WEATHER. The following table shows the distance at sea-level at which objects are visible at certain elevations: ELEVATION-FEET.

ELEVATION-FEET.

Miles.

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Normal Temperature and Rainfall

IN THE UNITED STATES.

TABLE SHOWING THE NORMAL TEMPERATURE FOR JANUARY AND JULY, AND THE NORMAL ANNUAL PRECIPITATION AT WEATHER BUREAU STATIONS IN EACH OF THE STATES AND TERRITORIES, ALSO THE HIGHEST AND LOWEST TEMPERATURES EVER REPORTED FROM EACH OF SAID STATIONS, TO DECEMBER 31, 1905.

(Prepared in the office of the Chief of the Weather Bureau, U. S. Department of Agriculture, for THE WORLD ALMANAC for 1907.)

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74 107-3518.3 19 76 106-3231.7 14 74 106-38 19.1 28 72 104-28 8.5 51 79 102 552.0 44 78 92 866.4 47 80 103 554.3 467 106-44 18.4 3 68 107 49 14.0 22 69 96 1141.9 32 72 99 742.7 34 74 96 747.2 28 74 100-1046.8 28 68 97 1314.2 34 68 95-1817.3 23 73 100-2-37.9 30 74 100 644.8 25 69 100-2335.0 33 78 105-1739.9 28 75 104-20 38.9 26 74 102-1630.9 35 82107 931.2 39 67 102-246.8 40 66 104 635.2 32 73 110 24 9.7 27 72 94 1641.3 32 76 103 639.8 30 74 103-2036.7 30 69 89 444.2 30 70 92-850.0 49 82 104 756.7 13 74 107-34 26. 8 41 78 101-10.55.0 40 81 104 953.3 38 80 104 1350.1 30 77 108-14 24.5 57 84 102 1836.9 44 82 113 5 9.3 43 82 104-646.5 30 73 93-97.6 28 76 102 -2016.2 1971 97-2528.8 36 78 102 642.8 40 79 102 252.1 30 68 109-2627.8 38 62 97-253.1 35 74 97-2546.9 15 73 104-4330.7 19 69 100-2532.1 1964 89-42 8.7 25 67 100-3812.2 10 67 100-5411.0

Weather Flags

OF THE WEATHER BUREAU, U. S. DEPARTMENT OF AGRICULTURE.

THE Weather Bureau furnishes, when practicable, for the benefit of all interests dependent upon weather conditions, the "Forecasts' which are prepared daily at the Central Office in Washington, D. C., and certain designated stations. These forecasts are telegraphed to stations of the Weather Bureau, railway officials, postmasters, and many others, to be communicated to the public by means of flags or steam whistles. The flags adopted for this purpose are five in number, and of the forms and colors indicated below:

No. 1. White Flag.

EXPLANATION OF WEATHER FLAGS.

No. 2. No. 3. No. 4. No. 5. Blue Flag. White and Blue Flag. Black Triangular Flag. White Flag with black square in centre.

Clear or fair weather.

Rain or snow. Local rain or snow.

Temperature.

Cold wave.

When number 4 is placed above number 1, 2, or 3, it indicates warmer; when below, colder; when not displayed, the temperature is expected to remain about stationary. During the late Spring and early Fall the cold-wave flag is also used to indicate anticipated frosts.

WHISTLE SIGNALS.

A warning blast of from fifteen to twenty seconds duration is sounded to attract attention. After this warning the longer blasts (of from four to six seconds duration) refer to weather, and shorter blasts (of from one to three seconds duration) refer to temperature; those for weather are sounded first.

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By repeating each combination a few times, with intervals of ten seconds, liability to error in reading the signals may be avoided.

As far as practicable the forecast messages will be telegraphed at the expense of the Weather Bureau; but if this is impracticable, they will be furnished at the regular commercial rates and sent "collect." In no case will the forecasts be sent to a second address in any place, except at the expense of the applicant.

Persons desiring to display the flags or sound the whistle signals for the benefit of the public should communicate with the Weather Bureau officials in charge of the climate and crop service of their respective States, the central stations of which are as follows:

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The Ancient and Modern Year.

THE Athenians began the year in June, the Macedonians in September, the Romans first in March and afterward in January, the Persians on August 11, the ancient Mexicans on February 23, the Mohammedans in July. The Chinese year, which begins early in February, is similar to the Mohammedan in having 12 months of 29 and 30 days alternately; but in every nineteen years there are seven years which have 13 months. This is not quite correct, and the Chinese have therefore formed a cycle of 60 years, in which period 22 intercalary months occur.

Storm and Hurricane Warnings

OF THE WEATHER BUREAU, U. S. DEPARTMENT OF AGRICULTURE. STORM WARNINGS.

Northeasterly winds. Southeasterly winds.

Northwesterly winds.

Southwesterly winds.

P

Red, black centre. Storm Warnings. -A red flag with a black centre indicates that a storm of marked violence is expected, The pennants displayed with the flags indicate the direction of the wind; red, easterly (from northeast to south); white, westerly (from southwest to north). The pennant above the flag indicates that the wind is expected to blow from the northerly quadrants; below, from the southerly quadrants. By night a red light indicates easterly winds, and a white light above a red light westerly winds. Hurricane Warnings. -Two red flags with black centres, displayed one above the other, indicate the expected approach of a tropical hurricane, and also one of those extremely severe and dangerous storms which occasionally move across the Lakes and Northern Atlantic Coast,

Velocity of Winds in the United States.

AVERAGE hourly velocity of the wind at selected stations of the United States Weather Bureau, also the highest velocity ever reported for a period of five minutes. (Prepared by W. L. Moore, Chief of the Weather Bureau, and revised to December 31, 1905, for THE WORLD ALMANAC.)

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Eastport, Me.....

97791679

Average

Hourly

Velocity.

Highest

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Reported.

STATIONS.

Mi.

Mi.

Mi.

El Paso, Texas....

5

78

Fort Smith, Ark...

5

64

Galveston, Texas

10 *84

Havre, Mont......

11

76

Red Bluff, Cal.....

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Jacksonville, Fla..

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Keokuk, Iowa...

8

60

Knoxville, Tenn...

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6 60

Leavenworth, Kan.t

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84 Louisville, Ky...........

7 58

Lynchburg, Va..

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Memphis, Tenn..

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Montgomery, Ala......

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Nashville, Tenn.

Philadelphia, Pa....
Pittsburgh, Pa.
Portland, Me..

Rochester, N. Y.
St. Louis, Mo......

St. Vincent, Minn.t..
Salt Lake City, Utah
San Diego, Cal...

San Francisco, Cal...
Santa Fé, N. M.....
Savannah, Ga.....
Spokane, Wash.

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Toledo, Ohio

New Orleans, La....

60

New York City, N.Y.

North Platte, Neb..

Omaha, Neb..

Palestine, Texas..

Washington, D. C.....
Wilmington, N. C......

*Anemometer blew away, at a velocity of 84 miles per hour, September,1900. †Stations discontinued. STANDARD TABLE SHOWING VELOCITY AND FORCE OF WINDS.

Force in

Vicksburg, Miss.....

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8 64

8 60

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4.428

35 3,080

51.3

6.027

Just perceptible......

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Gentle breeze..........

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044
Very high wind.....
.079
.123 Storm.

40 3,520

58.6

7.872

9.963

12.300

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492 22.0 1.107 29.3 1.968 36.6 3.075

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Brisk wind.......

45 3,960 66.0 50 4,400 73.3 60 5,280 70 6,160 102.7 24.108 80 7,040 117.3 31.488 100 8,800 146.6 49.200

From 1890 to 1898 the property loss by tornadoes in the United States was $26,633,750 [See THE WORLD ALMANAC for 1902, page 61]. The number of persons killed by tornadoes 1889 to 1898 inclusive was 1,437.

Loss by Lightning in the United States.

THE Weather Bureau of the United States Department of Agriculture in October, 1900, issued a bulletin giving these facts: In 1899 the total number of strokes of lightning which caused damage was 5,527; number of buildings injured, 6,256; value of property lost, $3,015,520: number of deaths by lightning during the year. 563; number of persons injured, 820; number of live stock killed in the fields, 4,251; value, $129,955. These are the latest available statistics.

The Chronicle Fire Tables record 3,012 fires caused by lightning in the United States in 1902, the property loss occasioned thereby being $3,396,810. These are the latest reported statistics on the subject.

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