Chapter III: Part 3

Clear, partly cloudy, cloudy, rain or snow indications are symbolized. The shaded area designates places or areas where precipitation has occurred during the preceding twelve hours.

WHAT THE WORDS “HIGH” OR “LOW” MEAN ON THE MAP

Low barometric pressure, or the storm centers, are indicated on the map by the word “low.” High barometric pressure centers are indicated by the word “high.” Note how they move in an easterly direction; how they are progressive. They can be compared to a series of waves, which we will call atmospheric waves. The crest of the wave may be likened to the “highs” and the troughs to the “lows.”

Usually the winds are southerly or easterly and therefore warmer in advance of a “low.” When the “lows” progress east of a place, the wind generally shifts to westerly and the temperature lowers. The westward advance of the “lows” is preceded by precipitation, and almost always in the form of rain or snow, following which the weather is generally clear. Note how a “low” is followed by a “high,” and so on as they move along eastwardly.

WHAT ISOTHERMS INDICATE

If the Isotherms run nearly parallel, that is, east and west, there will most likely be no change in the temperature. Southerly to east winds prevail west of the nearly north and south line, passing through the middle of a “high” and also east of a like line passing through the middle of a “low.”

To the west of a nearly north and south line passing through the middle of a “low,” northerly to westerly winds prevail. We will find the same condition prevailing to the east of a line passing through the center of a “high.”

Fig. 55
]

When we find an absence of decidedly energetic “lows” and “highs,” this is an indication of the continuance of existing weather. We can expect this state of the atmosphere until later maps show a beginning of a change, usually first appearing in the west.

TRACKS OF STORMS IN THE UNITED STATES

The storms of the United States follow, however, year after year, a series of tracks, not likely to change suddenly, and not irregular, but related to each other by very well-defined laws.

The United States Weather Bureau has made a very intensive study of the positions of the tracks of the storms. Fig. 55 shows the mean tracks and the movement of storms from day to day. This map indicates that generally there are two sets of lines running west and east, one set over the northwestern boundary, the Lake region, and the St. Lawrence Valley, the other set over the middle Rocky Mountain districts and the Gulf States. Each of these is double, with one for the “highs” and one for the “lows.” Furthermore, there are lines crossing from the main tracks to join them together, showing how storms pass from one to the other. On the chart, the heavy lines all belong to the tracks of the “highs,” and the lighter lines to the track of the “lows.”

THE MODE OF TRAVEL OF THE “HIGHS”

A “high” reaching the California coast may cross the mountains near Salt Lake City (follow the track on the map), and then pass directly over the belt of the Gulf States, turning northeastward and reaching the Virginia coast; or it may move farther northward, cross the Rocky Mountains in the State of Washington, up the Columbia River Valley, then turn east, and finally reach the Gulf of St. Lawrence. These tracks are located where they are by the laws of general circulation of the atmosphere and the outline of the North American continent. This movement of the “highs” from the middle Pacific coast to Florida or to the Gulf of St. Lawrence is confined to the summer half of the year, that is, from April to September. In the winter months, on the other hand, the source of the “highs” is different, though they reach the same terminals.

HISTORICAL FACTS

THERMOMETERS

Galileo discovered the principles of the thermometer in 1592. The Grand Duke of Tuscany, Ferdinand II, is given credit for perfecting it in 1610. Athanasius Kircher is given credit for the discovery of the mercurial thermometer. This was about 1641. Ferdinand the II, in 1650 or thereabouts, filled a glass tube with colored alcohol and hermetically sealed it after graduating the tube. Fahrenheit is given credit for the discovery that water freezes always at the same temperature. With these facts he devised a scale for thermometers in 1714.

THERMOMETER RECORDS

A temperature of 111° below zero has been recorded at an altitude of 48,700 feet in the United States.

The highest record in the United States Weather Bureau was taken in Death Valley, Cal., on June 30, July 1 and 2, 1891, when the thermometer reached 122° F. Death Valley is also given credit for the highest known monthly temperature, which was 102° F. in the month of July. Arctic expeditions have records of 73° and 66° below zero. This is the greatest natural cold recorded. The average temperature in the United States is 52.4°; the average temperature in England is 50°.

In the interior of Australia a record has been taken of a drop of 60° to 70° in a few hours; whereas the most rapid change recorded in the United States was 60° F. in twenty-four hours. This record has been made twice, in 1880 and again in 1890.

The lowest temperature recorded in the United States Weather Bureau was at Poplar River, Mont., January, 1885, when the thermometer registered 63° below zero.

The estimated heat of the sun is 10,000°; the highest artificial heat obtained is 7,000°. Regarding the heat of the sun, no definite conclusions have been arrived at, so the above temperature is only approximate.

REGIONS OF LEAST RELATIVE HUMIDITY

Least relative humidity is found in places southwest of Arizona, where the average is about 40°. Fifty degrees humidity means half as much moisture as is necessary for complete saturation. The average in other parts of the country is from 60° to 80°.

Steel boils at 3500°; water boils at 212°; liquid air submitted to a degree of cold where it ceases to be a gas and becomes a solid is 312° below zero. Professor John Dewar of England is credited with some of the most remarkable experiments with low temperature, and at these temperatures made some wonderful discoveries. He went down so cold that he could freeze liquid air back into a solid; he continued further until he reduced hydrogen, a very light gas, to a liquid. This was at 440° below zero. One of the most remarkable things he did was to freeze hydrogen into a solid.

Water boils at 183.2° Fahrenheit on top of Mt. Blanc; water boils at 194° Fahrenheit on top of Mt. Quito.

BAROMETERS

Torricelli is given credit for the discovery of the principles of the barometer. Otto Von Guericke, of Magdeburg, to whom we are indebted for the air pump, is credited as being the first person to use the barometer as a weather indicator.

Because of the fact that the mercurial barometer is not adaptable for portability, many scientists began work on producing a barometer without fluid that could be easily carried about and would give accurate results. In 1798 M. Comte, professor of aerostatics in the school at Meudon near Paris, invented the aneroid barometer, which he used in his balloon ascents. This instrument has been described fully on page 55.

BAROMETER RECORDS

Lowest reading taken in the United States by the United States Weather Bureau was 28.48, or practically three quarters of a pound per square inch below normal. Altitude records have been taken with the barometer as high as 85,270 feet. This record was made at Uccle Observatory, Belgium, the pressure being 0.67° at this point.

HAIL

Hail varies from one-tenth inch to more than five inches in diameter.

The following is an extract from the “Memoirs of Benvenuto Cellini” of a terrible hail storm in Lyons, France, in 1544: “The hail at length rose to the size of lemons. At about half a mile’s distance all the trees were broken down, and all the cattle were deprived of life; we likewise found a great many shepherds killed, and we saw hailstones which a man would have found it a difficult matter to have grasped in both hands.”

New Hampshire has the record for the largest hailstones seen here so far; they were 4 inches in diameter and weighed 18 ounces, and were 12½ inches in circumferences.

RAINFALL

There are records in Japan of where rain has reached 30 inches in twenty-four hours; in India where it has reached 40 inches in twenty-four hours.

The average rainfall in the United States is 35 inches.

There are certain places in India where the yearly rainfall averages over 470 inches; whereas other regions of India show less than 4 inches.

The higher the clouds are in the air, the larger the drops of rain when they reach the earth.

The heaviest annual rainfall recorded any place in the world is on the Khasi Hills in Bengal, where it registered 600 inches. The major part of this was in half of the year.

The greatest amount of rainfall is in the northwestern part of the United States; the least amount is in Arizona, the southwestern part. In some parts of Egypt and Arabia, the only moisture that is received there is in the form of dew.

The average cloudiness of the earth has been estimated between 50 and 55 per cent. This amount slightly exceeds the cloud conditions of the United States.

Unalaska has a record of extreme cloudiness for one whole month, February, 1880.

Sir J. C. Ross, an Arctic explorer, recorded a shower of nearly an hour’s duration on Christmas day, 1839, without a cloud in sight.

A similar record was made on June 30, 1877, at Vevay, Ind., where a shower lasted for five minutes in a cloudless sky.

A fall of yellow snow was recorded at South Bethlehem, Pa., in 1889. Examination showed this coloration to be due to the pollen of the pine trees which had been blown into the atmosphere before the fall.

Another record of yellow rainfall was recorded at Lynchburg on March 21, 1879.

Golden snow was recorded at Peckoloh, Germany, in 1877.

Green and red snows have been observed during Arctic explorations, due to a minute organism that was in the atmosphere.

When the temperature of the atmosphere is nearly 32° during a snow storm and the wind is blowing, the flakes being damp and the snowfall heavy, the flakes are apt to unite to form large masses of snow in the atmosphere or air, which accounts for some of the following records:

At Chapston, Wales, in January, 1888, the snowflakes measured 3.6 inches in length and 1.4 inches in breadth, and 1.3 inches in thickness. They amounted to 2½ cubic inches of water when melted.

There are some remarkable instances of where hailstones have cemented together, making large masses of ice. Some remarkable records of this kind have been recorded in India.

In Morganstown, Va., on April 28, 1877, hailstones 2 inches long and 1½ inches in diameter fell.

The mean yearly pressure of the United States ranges between 30 and 30.1 inches when reduced by ordinary methods to sea level.

In Unalaska, January 21, 1879, the barometer reading of 27.70 inches was recorded, and another low reading was made at Stykkisholm of 27.91 inches on February 1, 1877. On September 27, 1880, a ship on the China Sea experienced a terrific typhoon, during which the barometer went down in four hours from 29.64 to 27.04 inches.

The greatest temperature ranges recorded are in the interior of Siberia, where at Yakutsk they recorded a range of 181.4°.

The most remarkable changes recorded within twenty-four hours have been at Fort Maginnis, Mont., January 6, 1886, a fall of 56.40°; at Helena, Mont., January 6, 1886, a fall of 55° in sixteen hours; at Florence, Ariz., June 26, 1881, 65° rise. On the northern edge of the African desert the temperature of the air rose to 127.4°.

The lowest single temperature in the world was recorded at Werchojansk, Siberia, in January, 1885, when it was 90.4° below zero, while the average temperature for the month at the same place was 63.9° below zero.

Highest mean rainfall occurs in Sumatra, averaging about 130 inches; the rainfall of 493.2 inches per year occurs at Cherapunji, Assam, India, which is the largest in the world.

The lowest rainfall in the world occurs at Southeast California, West Arizona, and the valley of lower Colorado, where the rainfall averages less than 3 inches.

The most remarkable rainfall recorded in the United States for twenty-four hours occurred at Alexandria, La., June 15, 1886, when the rainfall reached the enormous amount of 21.4 inches. The most remarkable rainfall recorded in the world occurred at Purneah, Bengal, September 13, 1879, when the rainfall reached the unprecedented amount of 35 inches in twenty-four hours.

CLOUDBURSTS

On August 17, 1876, at Fort Sully, Dakota, occurred one of the heaviest cloudbursts ever known. The water moved out of the canyon on the opposite side of the Missouri in a solid bank three feet deep and 200 feet wide. There are many other remarkable cloudbursts recorded doing great injury, drowning and killing many people.

WIND VELOCITY

Among the most remarkable wind velocity records is that of Cape Lookout on October 17, 1879, when the wind blew at a rate of 138 miles an hour.

One of the worst cyclones ever recorded in North America was the flood, as it is usually termed, at Galveston, Tex. This storm began on the 1st day of September, 1900, and lasted until the 12th. It reached its maximum destructive force on the 8th. Six thousand lives were lost and $30,000,000 worth of property was destroyed.

Even worse than any of these was the one at Calcutta in 1864, followed by a storm wave over 16 feet high, causing a death-rate of 45,000 persons.

BLIZZARDS

The blizzard in Dakota of 1873 is one of the worst on record, but probably the most disastrous in the United States occurred in Montana, Dakota, and Texas on January 11, 1888. The loss of life exceeded 100 persons.

TORNADOES

The United States is more liable to tornadoes than any other part of the globe. In the United States over 3,000 people have been killed by tornadoes and thousands more have been injured. The greatest loss of lives recorded by tornadoes was at Adams City, Miss., on June 16, 1842, when 500 lives were lost.

The most remarkable hail storm was that of July 13, 1788, through France to Belgium, and did a property damage of over five million dollars.

There have been many destructive hailstorms in the United States. One on July 6, 1878, at central New York extended into parts of Massachusetts, Rhode Island and Connecticut. Stones fell recorded to measure 7 inches in diameter.

ROTARY MOTIONS OF STORMS

Benjamin Franklin has been given credit for the discovery that storms have a rotary motion, and that they move from west to east. This discovery was made in 1747.

Franklin did not positively prove these facts, and it remained for Redfield, Espy, Maury, Abbe to substantiate the truth of this statement.

THE FIRST UNITED STATES WEATHER BUREAU

The first United States Weather Bureau was established in 1870. General Albert J. Myer was the first chief of the United States Weather Bureau.

It is estimated that we are 250,000 miles from the moon.

At high altitudes, the cover of a kettle must be weighted down in order to boil an egg hard. This is to enable the pressure of steam to allow temperature high enough for boiling. In other words, it would be impossible to boil an egg in an open vessel at a high altitude.

------------------------------------------------------------------------

MEMORANDUM

Rain Tomorrow!

You do not like your ball game or picnic postponed just because of rain, do you? You want a bright day for that event. Then don’t guess what the weather will be on a certain day—know. Learn to use the

Gilbert Weather Bureau

to read weather indications from instruments set up by yourself—in your own home. This is an outfit you will like immensely. Made specially for your use and to provide you with a new kind of play.

The fun you get in making records of changes in temperature, in humidity, and in making forecasts will surely be great. Your boy friends will listen to you with interest when you explain to them the cause of storms and how important it is to have a knowledge of climatic disturbances. The outfits contain all the necessary equipment and a big book on weather, telling you how to know when it’s going to storm and many other interesting things. Your dealer will show you the Gilbert Weather Bureau Sets. If he hasn’t them, write

THE A. C. GILBERT COMPANY

514 Blatchley Avenue New Haven, Conn.

In Canada: THE A. C. GILBERT-MENZIES CO., Limited, Toronto, Ont.
In England: THE A. C. GILBERT CO., 125 High Holborn, London W.C. 1

WHAT IS SOUND?

Do you know that hearing is just feeling with the ear? That in reality, the thing we call sound, which we think of as a noise or as a musical note, is just an impression on the brain? Very few boys know this, and if you would like to be one of the few that do, you surely want an outfit of

Gilbert Sound Experiments

With one of these outfits you can find out just what sound is—how it is produced—why some pianos sound better than others—why a violin produces a musical tone, and many other things, including a number of startling table rapping tricks with which you can astonish your friends. A big book of instructions tells you how to perform every experiment. Get one of these outfits today. The best toy dealer in your town should have it; if not, write us and we’ll tell you where you can get it.

THE A. C. GILBERT COMPANY

514 BLATCHLEY AVE. NEW HAVEN, CONN.

In Canada: The A. C. Gilbert-Menzies Co., Limited, Toronto
In England: The A. C. Gilbert Co., 125 High Holborn, London, W. C. 2

In the Dark!

A knock on the head with a hatchet or a stab with a knife doesn’t sound pleasant, but you’ll enjoy apparent treatment of this kind and so will your friends who watch your shadow show. Make your boy friend rise in the air—change him into a bird or a cat—create freakish images. It’s easy! And laugh—your audience sure will enjoy it because it’s new—nothing like it. An entertainment made for boys who want real fun. But that’s only a few of the many things you can do with

GILBERT LIGHT EXPERIMENTS

One of these outfits will help you to understand a great many facts
about light. You can perform a number of experiments which explain the
laws of light. Learn about the movie machine, the telescope and other
optical instruments. There’s a big book on Light with each set, it’s a
handy size, just right to put in your pocket.

From this book and your set you’ll get a knowledge of light that will
be helpful to you always. It’s great fun too, the kind you like. The
outfit is complete with prisms, mirrors and all the apparatus you’ll
need to perform the experiments.

_Ask your dealer to show you this new Gilbert toy._
_If he hasn’t it write_

THE A. C. GILBERT COMPANY

514 Blatchley Ave., New Haven, Conn.

In Canada—The A. C. Gilbert-Menzies Co., Limited, Toronto, Ont.
In England—The A. C. Gilbert Co., 125 High Holborn, London, W. C. 1

_The Most Helpful Book for Boys Ever Published_

Think of it! “Football Strategy,” by Walter Camp—“How to Pole Vault,” by Former World’s Champion, A. C. Gilbert—“Flying,” by Eddie Rickenbacker, and “Athletic Training,” by the famous Yale trainer, Johnny Mack. Chapters about signalling, wireless, wonderful heat, sound and light experiments, how to build a real weather bureau station of your own, chemistry for boys, electrical, hydraulic and pneumatic engineering and surveying, practical carpentry—all in one finely illustrated book. It’s yours for a quarter and worth dollars to you.

_The Greatest Book for Boys in Years_

_Buy it from your dealer, or send us 25c today. You’ll never be sorry_

The A. C. Gilbert Company

514 Blatchley Avenue
New Haven : Conn.

------------------------------------------------------------------------

TRANSCRIBER’S NOTES

1. P. 67, changed “it means that there is one one-hundredth of an inch of rain” to “it means that there is one one-tenth of an inch of rain”. [Makes the math consistent with the rest of the section.] 2. P. 68, changed “by one hundred for actual rainfall” to “by ten for actual rainfall”. [Makes the math consistent with the rest of the section.] 3. Silently corrected obvious typographical errors and variations in spelling. 4. Retained archaic, non-standard, and uncertain spellings as printed. 5. Enclosed italics font in _underscores_. 6. Enclosed bold font in =equals=.